ensure token matches

lib/pleroma/web/o_auth/o_auth_controller.ex

@@ -71,16 +71,27 @@ def authorize(
 
   def authorize(%Plug.Conn{} = conn, params), do: do_authorize(conn, params)
 
+  defp maybe_remove_token(%Plug.Conn{assigns: %{token: %{app: id}}} = conn, %App{id: id}) do
+    conn
+  end
+
+  defp maybe_remove_token(conn, _app) do
+    conn
+    |> assign(:token, nil)
+  end
+
   defp do_authorize(%Plug.Conn{} = conn, params) do
     app = Repo.get_by(App, client_id: params["client_id"])
+    conn = maybe_remove_token(conn, app)
     available_scopes = (app && app.scopes) || []
     scopes = Scopes.fetch_scopes(params, available_scopes)
 
     # if we already have a token for this specific setup, we can use that
     with false <- Params.truthy_param?(params["force_login"]),
          %App{} <- app,
-         {:ok, _} <- Scopes.validate(scopes, app.scopes),
+         %{assigns: %{user: %Pleroma.User{} = user}} <- conn,
-         {:ok, %Token{} = token} <- Token.get_by_app(app) do
+         {:ok, %Token{} = token} <- Token.get_preexisting_by_app_and_user(app, user),
+         true <- scopes == token.scopes do
       token = Repo.preload(token, :app)
 
       conn

lib/pleroma/web/o_auth/token.ex

@@ -39,9 +39,9 @@ def get_by_token(token) do
     |> Repo.find_resource()
   end
 
-  def get_by_app(%App{} = app) do
+  def get_preexisting_by_app_and_user(%App{} = app, %User{} = user) do
     app.id
-    |> Query.get_unexpired_by_app()
+    |> Query.get_unexpired_by_app_and_user(user)
     |> Repo.find_resource()
   end
 

lib/pleroma/web/o_auth/token/query.ex

@@ -23,10 +23,14 @@ def get_by_token(query \\ Token, token) do
     from(q in query, where: q.token == ^token)
   end
 
-  @spec get_unexpired_by_app(query, String.t()) :: query
+  @spec get_unexpired_by_app_and_user(query, String.t()) :: query
-  def get_unexpired_by_app(query \\ Token, app_id) do
+  def get_unexpired_by_app_and_user(query \\ Token, app_id, %Pleroma.User{id: user_id}) do
     time = NaiveDateTime.utc_now()
-    from(q in query, where: q.app_id == ^app_id and q.valid_until > ^time, limit: 1)
+
+    from(q in query,
+      where: q.app_id == ^app_id and q.valid_until > ^time and q.user_id == ^user_id,
+      limit: 1
+    )
   end
 
   @spec get_by_app(query, String.t()) :: query

test/pleroma/web/o_auth/o_auth_controller_test.exs

@@ -470,12 +470,17 @@ test "renders authentication page if user is already authenticated but `force_lo
       assert html_response(conn, 200) =~ ~s(type="submit")
     end
 
-    test "renders authentication page if user is already authenticated but user request with another client",
+    test "reuses authentication if the user is authenticated with another client",
          %{
-           app: app,
            conn: conn
          } do
-      token = insert(:oauth_token, app: app)
+      user = insert(:user)
+
+      app = insert(:oauth_app, redirect_uris: "https://redirect.url")
+      other_app = insert(:oauth_app, redirect_uris: "https://redirect.url")
+
+      token = insert(:oauth_token, user: user, app: app)
+      reusable_token = insert(:oauth_token, app: other_app, user: user)
 
       conn =
         conn
@@ -484,12 +489,111 @@ test "renders authentication page if user is already authenticated but user requ
           "/oauth/authorize",
           %{
             "response_type" => "code",
-            "client_id" => "another_client_id",
+            "client_id" => other_app.client_id,
-            "redirect_uri" => OAuthController.default_redirect_uri(app),
+            "redirect_uri" => OAuthController.default_redirect_uri(other_app),
             "scope" => "read"
           }
         )
 
+      assert URI.decode(redirected_to(conn)) ==
+               "https://redirect.url?access_token=#{reusable_token.token}"
+    end
+
+    test "does not reuse other people's tokens",
+         %{
+           conn: conn
+         } do
+      user = insert(:user)
+      other_user = insert(:user)
+
+      app = insert(:oauth_app, redirect_uris: "https://redirect.url")
+      other_app = insert(:oauth_app, redirect_uris: "https://redirect.url")
+
+      token = insert(:oauth_token, user: user, app: app)
+      _not_reusable_token = insert(:oauth_token, app: other_app, user: other_user)
+
+      conn =
+        conn
+        |> put_req_header("authorization", "Bearer #{token.token}")
+        |> get(
+          "/oauth/authorize",
+          %{
+            "response_type" => "code",
+            "client_id" => other_app.client_id,
+            "redirect_uri" => OAuthController.default_redirect_uri(other_app),
+            "scope" => "read"
+          }
+        )
+
+      assert html_response(conn, 200) =~ ~s(type="submit")
+    end
+
+    test "does not reuse expired tokens",
+         %{
+           conn: conn
+         } do
+      user = insert(:user)
+
+      app = insert(:oauth_app, redirect_uris: "https://redirect.url")
+
+      other_app = insert(:oauth_app, redirect_uris: "https://redirect.url")
+
+      token = insert(:oauth_token, user: user, app: app)
+
+      _not_reusable_token =
+        insert(:oauth_token,
+          app: other_app,
+          user: user,
+          valid_until: NaiveDateTime.add(NaiveDateTime.utc_now(), -60 * 100)
+        )
+
+      conn =
+        conn
+        |> put_req_header("authorization", "Bearer #{token.token}")
+        |> get(
+          "/oauth/authorize",
+          %{
+            "response_type" => "code",
+            "client_id" => other_app.client_id,
+            "redirect_uri" => OAuthController.default_redirect_uri(other_app),
+            "scope" => "read"
+          }
+        )
+
+      assert html_response(conn, 200) =~ ~s(type="submit")
+    end
+
+    test "does not reuse tokens with the wrong scopes",
+         %{
+           conn: conn
+         } do
+      user = insert(:user)
+
+      app = insert(:oauth_app, redirect_uris: "https://redirect.url")
+
+      other_app = insert(:oauth_app, redirect_uris: "https://redirect.url")
+
+      token = insert(:oauth_token, user: user, app: app, scopes: ["read"])
+
+      _not_reusable_token =
+        insert(:oauth_token,
+          app: other_app,
+          user: user
+        )
+
+      conn =
+        conn
+        |> put_req_header("authorization", "Bearer #{token.token}")
+        |> get(
+          "/oauth/authorize",
+          %{
+            "response_type" => "code",
+            "client_id" => other_app.client_id,
+            "redirect_uri" => OAuthController.default_redirect_uri(other_app),
+            "scope" => "read write"
+          }
+        )
+
       assert html_response(conn, 200) =~ ~s(type="submit")
     end