Merge branch 'release/2.2.0' into 'stable'v2.2.0

Release/2.2.0

See merge request pleroma/secteam/pleroma!19

1 files changed, 613 insertions, 0 deletions

diff --git a/lib/pleroma/web/o_auth/o_auth_controller.ex b/lib/pleroma/web/o_auth/o_auth_controller.ex
new file mode 100644
index 000000000..d2f9d1ceb
--- /dev/null
+++ b/lib/pleroma/web/o_auth/o_auth_controller.ex
@@ -0,0 +1,613 @@
+# Pleroma: A lightweight social networking server
+# Copyright © 2017-2020 Pleroma Authors <https://pleroma.social/>
+# SPDX-License-Identifier: AGPL-3.0-only
+
+defmodule Pleroma.Web.OAuth.OAuthController do
+  use Pleroma.Web, :controller
+
+  alias Pleroma.Helpers.UriHelper
+  alias Pleroma.Maps
+  alias Pleroma.MFA
+  alias Pleroma.Registration
+  alias Pleroma.Repo
+  alias Pleroma.User
+  alias Pleroma.Web.Auth.Authenticator
+  alias Pleroma.Web.ControllerHelper
+  alias Pleroma.Web.OAuth.App
+  alias Pleroma.Web.OAuth.Authorization
+  alias Pleroma.Web.OAuth.MFAController
+  alias Pleroma.Web.OAuth.MFAView
+  alias Pleroma.Web.OAuth.OAuthView
+  alias Pleroma.Web.OAuth.Scopes
+  alias Pleroma.Web.OAuth.Token
+  alias Pleroma.Web.OAuth.Token.Strategy.RefreshToken
+  alias Pleroma.Web.OAuth.Token.Strategy.Revoke, as: RevokeToken
+  alias Pleroma.Web.Plugs.RateLimiter
+
+  require Logger
+
+  if Pleroma.Config.oauth_consumer_enabled?(), do: plug(Ueberauth)
+
+  plug(:fetch_session)
+  plug(:fetch_flash)
+
+  plug(:skip_plug, [
+    Pleroma.Web.Plugs.OAuthScopesPlug,
+    Pleroma.Web.Plugs.EnsurePublicOrAuthenticatedPlug
+  ])
+
+  plug(RateLimiter, [name: :authentication] when action == :create_authorization)
+
+  action_fallback(Pleroma.Web.OAuth.FallbackController)
+
+  @oob_token_redirect_uri "urn:ietf:wg:oauth:2.0:oob"
+
+  # Note: this definition is only called from error-handling methods with `conn.params` as 2nd arg
+  def authorize(%Plug.Conn{} = conn, %{"authorization" => _} = params) do
+    {auth_attrs, params} = Map.pop(params, "authorization")
+    authorize(conn, Map.merge(params, auth_attrs))
+  end
+
+  def authorize(%Plug.Conn{assigns: %{token: %Token{}}} = conn, %{"force_login" => _} = params) do
+    if ControllerHelper.truthy_param?(params["force_login"]) do
+      do_authorize(conn, params)
+    else
+      handle_existing_authorization(conn, params)
+    end
+  end
+
+  # Note: the token is set in oauth_plug, but the token and client do not always go together.
+  # For example, MastodonFE's token is set if user requests with another client,
+  # after user already authorized to MastodonFE.
+  # So we have to check client and token.
+  def authorize(
+        %Plug.Conn{assigns: %{token: %Token{} = token}} = conn,
+        %{"client_id" => client_id} = params
+      ) do
+    with %Token{} = t <- Repo.get_by(Token, token: token.token) |> Repo.preload(:app),
+         ^client_id <- t.app.client_id do
+      handle_existing_authorization(conn, params)
+    else
+      _ -> do_authorize(conn, params)
+    end
+  end
+
+  def authorize(%Plug.Conn{} = conn, params), do: do_authorize(conn, params)
+
+  defp do_authorize(%Plug.Conn{} = conn, params) do
+    app = Repo.get_by(App, client_id: params["client_id"])
+    available_scopes = (app && app.scopes) || []
+    scopes = Scopes.fetch_scopes(params, available_scopes)
+
+    scopes =
+      if scopes == [] do
+        available_scopes
+      else
+        scopes
+      end
+
+    # Note: `params` might differ from `conn.params`; use `@params` not `@conn.params` in template
+    render(conn, Authenticator.auth_template(), %{
+      response_type: params["response_type"],
+      client_id: params["client_id"],
+      available_scopes: available_scopes,
+      scopes: scopes,
+      redirect_uri: params["redirect_uri"],
+      state: params["state"],
+      params: params
+    })
+  end
+
+  defp handle_existing_authorization(
+         %Plug.Conn{assigns: %{token: %Token{} = token}} = conn,
+         %{"redirect_uri" => @oob_token_redirect_uri}
+       ) do
+    render(conn, "oob_token_exists.html", %{token: token})
+  end
+
+  defp handle_existing_authorization(
+         %Plug.Conn{assigns: %{token: %Token{} = token}} = conn,
+         %{} = params
+       ) do
+    app = Repo.preload(token, :app).app
+
+    redirect_uri =
+      if is_binary(params["redirect_uri"]) do
+        params["redirect_uri"]
+      else
+        default_redirect_uri(app)
+      end
+
+    if redirect_uri in String.split(app.redirect_uris) do
+      redirect_uri = redirect_uri(conn, redirect_uri)
+      url_params = %{access_token: token.token}
+      url_params = Maps.put_if_present(url_params, :state, params["state"])
+      url = UriHelper.modify_uri_params(redirect_uri, url_params)
+      redirect(conn, external: url)
+    else
+      conn
+      |> put_flash(:error, dgettext("errors", "Unlisted redirect_uri."))
+      |> redirect(external: redirect_uri(conn, redirect_uri))
+    end
+  end
+
+  def create_authorization(
+        %Plug.Conn{} = conn,
+        %{"authorization" => _} = params,
+        opts \\ []
+      ) do
+    with {:ok, auth, user} <- do_create_authorization(conn, params, opts[:user]),
+         {:mfa_required, _, _, false} <- {:mfa_required, user, auth, MFA.require?(user)} do
+      after_create_authorization(conn, auth, params)
+    else
+      error ->
+        handle_create_authorization_error(conn, error, params)
+    end
+  end
+
+  def after_create_authorization(%Plug.Conn{} = conn, %Authorization{} = auth, %{
+        "authorization" => %{"redirect_uri" => @oob_token_redirect_uri}
+      }) do
+    # Enforcing the view to reuse the template when calling from other controllers
+    conn
+    |> put_view(OAuthView)
+    |> render("oob_authorization_created.html", %{auth: auth})
+  end
+
+  def after_create_authorization(%Plug.Conn{} = conn, %Authorization{} = auth, %{
+        "authorization" => %{"redirect_uri" => redirect_uri} = auth_attrs
+      }) do
+    app = Repo.preload(auth, :app).app
+
+    # An extra safety measure before we redirect (also done in `do_create_authorization/2`)
+    if redirect_uri in String.split(app.redirect_uris) do
+      redirect_uri = redirect_uri(conn, redirect_uri)
+      url_params = %{code: auth.token}
+      url_params = Maps.put_if_present(url_params, :state, auth_attrs["state"])
+      url = UriHelper.modify_uri_params(redirect_uri, url_params)
+      redirect(conn, external: url)
+    else
+      conn
+      |> put_flash(:error, dgettext("errors", "Unlisted redirect_uri."))
+      |> redirect(external: redirect_uri(conn, redirect_uri))
+    end
+  end
+
+  defp handle_create_authorization_error(
+         %Plug.Conn{} = conn,
+         {:error, scopes_issue},
+         %{"authorization" => _} = params
+       )
+       when scopes_issue in [:unsupported_scopes, :missing_scopes] do
+    # Per https://github.com/tootsuite/mastodon/blob/
+    #   51e154f5e87968d6bb115e053689767ab33e80cd/app/controllers/api/base_controller.rb#L39
+    conn
+    |> put_flash(:error, dgettext("errors", "This action is outside the authorized scopes"))
+    |> put_status(:unauthorized)
+    |> authorize(params)
+  end
+
+  defp handle_create_authorization_error(
+         %Plug.Conn{} = conn,
+         {:account_status, :confirmation_pending},
+         %{"authorization" => _} = params
+       ) do
+    conn
+    |> put_flash(:error, dgettext("errors", "Your login is missing a confirmed e-mail address"))
+    |> put_status(:forbidden)
+    |> authorize(params)
+  end
+
+  defp handle_create_authorization_error(
+         %Plug.Conn{} = conn,
+         {:mfa_required, user, auth, _},
+         params
+       ) do
+    {:ok, token} = MFA.Token.create(user, auth)
+
+    data = %{
+      "mfa_token" => token.token,
+      "redirect_uri" => params["authorization"]["redirect_uri"],
+      "state" => params["authorization"]["state"]
+    }
+
+    MFAController.show(conn, data)
+  end
+
+  defp handle_create_authorization_error(
+         %Plug.Conn{} = conn,
+         {:account_status, :password_reset_pending},
+         %{"authorization" => _} = params
+       ) do
+    conn
+    |> put_flash(:error, dgettext("errors", "Password reset is required"))
+    |> put_status(:forbidden)
+    |> authorize(params)
+  end
+
+  defp handle_create_authorization_error(
+         %Plug.Conn{} = conn,
+         {:account_status, :deactivated},
+         %{"authorization" => _} = params
+       ) do
+    conn
+    |> put_flash(:error, dgettext("errors", "Your account is currently disabled"))
+    |> put_status(:forbidden)
+    |> authorize(params)
+  end
+
+  defp handle_create_authorization_error(%Plug.Conn{} = conn, error, %{"authorization" => _}) do
+    Authenticator.handle_error(conn, error)
+  end
+
+  @doc "Renew access_token with refresh_token"
+  def token_exchange(
+        %Plug.Conn{} = conn,
+        %{"grant_type" => "refresh_token", "refresh_token" => token} = _params
+      ) do
+    with {:ok, app} <- Token.Utils.fetch_app(conn),
+         {:ok, %{user: user} = token} <- Token.get_by_refresh_token(app, token),
+         {:ok, token} <- RefreshToken.grant(token) do
+      json(conn, OAuthView.render("token.json", %{user: user, token: token}))
+    else
+      _error -> render_invalid_credentials_error(conn)
+    end
+  end
+
+  def token_exchange(%Plug.Conn{} = conn, %{"grant_type" => "authorization_code"} = params) do
+    with {:ok, app} <- Token.Utils.fetch_app(conn),
+         fixed_token = Token.Utils.fix_padding(params["code"]),
+         {:ok, auth} <- Authorization.get_by_token(app, fixed_token),
+         %User{} = user <- User.get_cached_by_id(auth.user_id),
+         {:ok, token} <- Token.exchange_token(app, auth) do
+      json(conn, OAuthView.render("token.json", %{user: user, token: token}))
+    else
+      error ->
+        handle_token_exchange_error(conn, error)
+    end
+  end
+
+  def token_exchange(
+        %Plug.Conn{} = conn,
+        %{"grant_type" => "password"} = params
+      ) do
+    with {:ok, %User{} = user} <- Authenticator.get_user(conn),
+         {:ok, app} <- Token.Utils.fetch_app(conn),
+         requested_scopes <- Scopes.fetch_scopes(params, app.scopes),
+         {:ok, token} <- login(user, app, requested_scopes) do
+      json(conn, OAuthView.render("token.json", %{user: user, token: token}))
+    else
+      error ->
+        handle_token_exchange_error(conn, error)
+    end
+  end
+
+  def token_exchange(
+        %Plug.Conn{} = conn,
+        %{"grant_type" => "password", "name" => name, "password" => _password} = params
+      ) do
+    params =
+      params
+      |> Map.delete("name")
+      |> Map.put("username", name)
+
+    token_exchange(conn, params)
+  end
+
+  def token_exchange(%Plug.Conn{} = conn, %{"grant_type" => "client_credentials"} = _params) do
+    with {:ok, app} <- Token.Utils.fetch_app(conn),
+         {:ok, auth} <- Authorization.create_authorization(app, %User{}),
+         {:ok, token} <- Token.exchange_token(app, auth) do
+      json(conn, OAuthView.render("token.json", %{token: token}))
+    else
+      _error ->
+        handle_token_exchange_error(conn, :invalid_credentails)
+    end
+  end
+
+  # Bad request
+  def token_exchange(%Plug.Conn{} = conn, params), do: bad_request(conn, params)
+
+  defp handle_token_exchange_error(%Plug.Conn{} = conn, {:mfa_required, user, auth, _}) do
+    conn
+    |> put_status(:forbidden)
+    |> json(build_and_response_mfa_token(user, auth))
+  end
+
+  defp handle_token_exchange_error(%Plug.Conn{} = conn, {:account_status, :deactivated}) do
+    render_error(
+      conn,
+      :forbidden,
+      "Your account is currently disabled",
+      %{},
+      "account_is_disabled"
+    )
+  end
+
+  defp handle_token_exchange_error(
+         %Plug.Conn{} = conn,
+         {:account_status, :password_reset_pending}
+       ) do
+    render_error(
+      conn,
+      :forbidden,
+      "Password reset is required",
+      %{},
+      "password_reset_required"
+    )
+  end
+
+  defp handle_token_exchange_error(%Plug.Conn{} = conn, {:account_status, :confirmation_pending}) do
+    render_error(
+      conn,
+      :forbidden,
+      "Your login is missing a confirmed e-mail address",
+      %{},
+      "missing_confirmed_email"
+    )
+  end
+
+  defp handle_token_exchange_error(%Plug.Conn{} = conn, {:account_status, :approval_pending}) do
+    render_error(
+      conn,
+      :forbidden,
+      "Your account is awaiting approval.",
+      %{},
+      "awaiting_approval"
+    )
+  end
+
+  defp handle_token_exchange_error(%Plug.Conn{} = conn, _error) do
+    render_invalid_credentials_error(conn)
+  end
+
+  def token_revoke(%Plug.Conn{} = conn, %{"token" => _token} = params) do
+    with {:ok, app} <- Token.Utils.fetch_app(conn),
+         {:ok, _token} <- RevokeToken.revoke(app, params) do
+      json(conn, %{})
+    else
+      _error ->
+        # RFC 7009: invalid tokens [in the request] do not cause an error response
+        json(conn, %{})
+    end
+  end
+
+  def token_revoke(%Plug.Conn{} = conn, params), do: bad_request(conn, params)
+
+  # Response for bad request
+  defp bad_request(%Plug.Conn{} = conn, _) do
+    render_error(conn, :internal_server_error, "Bad request")
+  end
+
+  @doc "Prepares OAuth request to provider for Ueberauth"
+  def prepare_request(%Plug.Conn{} = conn, %{
+        "provider" => provider,
+        "authorization" => auth_attrs
+      }) do
+    scope =
+      auth_attrs
+      |> Scopes.fetch_scopes([])
+      |> Scopes.to_string()
+
+    state =
+      auth_attrs
+      |> Map.delete("scopes")
+      |> Map.put("scope", scope)
+      |> Jason.encode!()
+
+    params =
+      auth_attrs
+      |> Map.drop(~w(scope scopes client_id redirect_uri))
+      |> Map.put("state", state)
+
+    # Handing the request to Ueberauth
+    redirect(conn, to: o_auth_path(conn, :request, provider, params))
+  end
+
+  def request(%Plug.Conn{} = conn, params) do
+    message =
+      if params["provider"] do
+        dgettext("errors", "Unsupported OAuth provider: %{provider}.",
+          provider: params["provider"]
+        )
+      else
+        dgettext("errors", "Bad OAuth request.")
+      end
+
+    conn
+    |> put_flash(:error, message)
+    |> redirect(to: "/")
+  end
+
+  def callback(%Plug.Conn{assigns: %{ueberauth_failure: failure}} = conn, params) do
+    params = callback_params(params)
+    messages = for e <- Map.get(failure, :errors, []), do: e.message
+    message = Enum.join(messages, "; ")
+
+    conn
+    |> put_flash(
+      :error,
+      dgettext("errors", "Failed to authenticate: %{message}.", message: message)
+    )
+    |> redirect(external: redirect_uri(conn, params["redirect_uri"]))
+  end
+
+  def callback(%Plug.Conn{} = conn, params) do
+    params = callback_params(params)
+
+    with {:ok, registration} <- Authenticator.get_registration(conn) do
+      auth_attrs = Map.take(params, ~w(client_id redirect_uri scope scopes state))
+
+      case Repo.get_assoc(registration, :user) do
+        {:ok, user} ->
+          create_authorization(conn, %{"authorization" => auth_attrs}, user: user)
+
+        _ ->
+          registration_params =
+            Map.merge(auth_attrs, %{
+              "nickname" => Registration.nickname(registration),
+              "email" => Registration.email(registration)
+            })
+
+          conn
+          |> put_session_registration_id(registration.id)
+          |> registration_details(%{"authorization" => registration_params})
+      end
+    else
+      error ->
+        Logger.debug(inspect(["OAUTH_ERROR", error, conn.assigns]))
+
+        conn
+        |> put_flash(:error, dgettext("errors", "Failed to set up user account."))
+        |> redirect(external: redirect_uri(conn, params["redirect_uri"]))
+    end
+  end
+
+  defp callback_params(%{"state" => state} = params) do
+    Map.merge(params, Jason.decode!(state))
+  end
+
+  def registration_details(%Plug.Conn{} = conn, %{"authorization" => auth_attrs}) do
+    render(conn, "register.html", %{
+      client_id: auth_attrs["client_id"],
+      redirect_uri: auth_attrs["redirect_uri"],
+      state: auth_attrs["state"],
+      scopes: Scopes.fetch_scopes(auth_attrs, []),
+      nickname: auth_attrs["nickname"],
+      email: auth_attrs["email"]
+    })
+  end
+
+  def register(%Plug.Conn{} = conn, %{"authorization" => _, "op" => "connect"} = params) do
+    with registration_id when not is_nil(registration_id) <- get_session_registration_id(conn),
+         %Registration{} = registration <- Repo.get(Registration, registration_id),
+         {_, {:ok, auth, _user}} <-
+           {:create_authorization, do_create_authorization(conn, params)},
+         %User{} = user <- Repo.preload(auth, :user).user,
+         {:ok, _updated_registration} <- Registration.bind_to_user(registration, user) do
+      conn
+      |> put_session_registration_id(nil)
+      |> after_create_authorization(auth, params)
+    else
+      {:create_authorization, error} ->
+        {:register, handle_create_authorization_error(conn, error, params)}
+
+      _ ->
+        {:register, :generic_error}
+    end
+  end
+
+  def register(%Plug.Conn{} = conn, %{"authorization" => _, "op" => "register"} = params) do
+    with registration_id when not is_nil(registration_id) <- get_session_registration_id(conn),
+         %Registration{} = registration <- Repo.get(Registration, registration_id),
+         {:ok, user} <- Authenticator.create_from_registration(conn, registration) do
+      conn
+      |> put_session_registration_id(nil)
+      |> create_authorization(
+        params,
+        user: user
+      )
+    else
+      {:error, changeset} ->
+        message =
+          Enum.map(changeset.errors, fn {field, {error, _}} ->
+            "#{field} #{error}"
+          end)
+          |> Enum.join("; ")
+
+        message =
+          String.replace(
+            message,
+            "ap_id has already been taken",
+            "nickname has already been taken"
+          )
+
+        conn
+        |> put_status(:forbidden)
+        |> put_flash(:error, "Error: #{message}.")
+        |> registration_details(params)
+
+      _ ->
+        {:register, :generic_error}
+    end
+  end
+
+  defp do_create_authorization(conn, auth_attrs, user \\ nil)
+
+  defp do_create_authorization(
+         %Plug.Conn{} = conn,
+         %{
+           "authorization" =>
+             %{
+               "client_id" => client_id,
+               "redirect_uri" => redirect_uri
+             } = auth_attrs
+         },
+         user
+       ) do
+    with {_, {:ok, %User{} = user}} <-
+           {:get_user, (user && {:ok, user}) || Authenticator.get_user(conn)},
+         %App{} = app <- Repo.get_by(App, client_id: client_id),
+         true <- redirect_uri in String.split(app.redirect_uris),
+         requested_scopes <- Scopes.fetch_scopes(auth_attrs, app.scopes),
+         {:ok, auth} <- do_create_authorization(user, app, requested_scopes) do
+      {:ok, auth, user}
+    end
+  end
+
+  defp do_create_authorization(%User{} = user, %App{} = app, requested_scopes)
+       when is_list(requested_scopes) do
+    with {:account_status, :active} <- {:account_status, User.account_status(user)},
+         {:ok, scopes} <- validate_scopes(app, requested_scopes),
+         {:ok, auth} <- Authorization.create_authorization(app, user, scopes) do
+      {:ok, auth}
+    end
+  end
+
+  # Note: intended to be a private function but opened for AccountController that logs in on signup
+  @doc "If checks pass, creates authorization and token for given user, app and requested scopes."
+  def login(%User{} = user, %App{} = app, requested_scopes) when is_list(requested_scopes) do
+    with {:ok, auth} <- do_create_authorization(user, app, requested_scopes),
+         {:mfa_required, _, _, false} <- {:mfa_required, user, auth, MFA.require?(user)},
+         {:ok, token} <- Token.exchange_token(app, auth) do
+      {:ok, token}
+    end
+  end
+
+  # Special case: Local MastodonFE
+  defp redirect_uri(%Plug.Conn{} = conn, "."), do: auth_url(conn, :login)
+
+  defp redirect_uri(%Plug.Conn{}, redirect_uri), do: redirect_uri
+
+  defp get_session_registration_id(%Plug.Conn{} = conn), do: get_session(conn, :registration_id)
+
+  defp put_session_registration_id(%Plug.Conn{} = conn, registration_id),
+    do: put_session(conn, :registration_id, registration_id)
+
+  defp build_and_response_mfa_token(user, auth) do
+    with {:ok, token} <- MFA.Token.create(user, auth) do
+      MFAView.render("mfa_response.json", %{token: token, user: user})
+    end
+  end
+
+  @spec validate_scopes(App.t(), map() | list()) ::
+          {:ok, list()} | {:error, :missing_scopes | :unsupported_scopes}
+  defp validate_scopes(%App{} = app, params) when is_map(params) do
+    requested_scopes = Scopes.fetch_scopes(params, app.scopes)
+    validate_scopes(app, requested_scopes)
+  end
+
+  defp validate_scopes(%App{} = app, requested_scopes) when is_list(requested_scopes) do
+    Scopes.validate(requested_scopes, app.scopes)
+  end
+
+  def default_redirect_uri(%App{} = app) do
+    app.redirect_uris
+    |> String.split()
+    |> Enum.at(0)
+  end
+
+  defp render_invalid_credentials_error(conn) do
+    render_error(conn, :bad_request, "Invalid credentials")
+  end
+end