akkoma/lib/pleroma/web/o_auth/o_auth_controller.ex
2023-12-17 21:48:19 +00:00

667 lines
22 KiB
Elixir

# Pleroma: A lightweight social networking server
# Copyright © 2017-2021 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.AuthHelper
alias Pleroma.Helpers.UriHelper
alias Pleroma.Maps
alias Pleroma.MFA
alias Pleroma.Registration
alias Pleroma.Repo
alias Pleroma.User
alias Pleroma.Web.Auth.WrapperAuthenticator, as: Authenticator
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
alias Pleroma.Web.Utils.Params
require Logger
if Pleroma.Config.oauth_consumer_enabled?(), do: plug(Ueberauth)
plug(:fetch_session)
plug(:fetch_flash)
plug(:skip_auth)
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"
@state_cookie_name "akkoma_oauth_state"
# 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 Params.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, user: %User{} = user}} = 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
_ ->
maybe_reuse_token(conn, params, user.id)
end
end
def authorize(%Plug.Conn{} = conn, params) do
# if we have a user in the session, attempt to authenticate as them
# otherwise show the login form
maybe_reuse_token(conn, params, AuthHelper.get_session_user(conn))
end
defp maybe_reuse_token(conn, params, user_id) when is_binary(user_id) do
with %User{} = user <- User.get_cached_by_id(user_id),
%App{} = app <- Repo.get_by(App, client_id: params["client_id"]),
{:ok, %Token{} = token} <- Token.get_preeexisting_by_app_and_user(app, user),
{:ok, %Authorization{} = auth} <-
Authorization.get_preeexisting_by_app_and_user(app, user) do
conn
|> assign(:token, token)
|> after_create_authorization(auth, %{"authorization" => params})
else
_ -> do_authorize(conn, params)
end
end
defp maybe_reuse_token(conn, params, _user), 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)
user =
with %{assigns: %{user: %User{} = user}} <- conn do
user
else
_ -> nil
end
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(), %{
user: user,
app: app && Map.delete(app, :client_secret),
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,
view_module: OAuthView
})
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(_, _, opts \\ [])
def create_authorization(%Plug.Conn{assigns: %{user: %User{} = user}} = conn, params, []) do
create_authorization(conn, params, user: user)
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
conn
|> AuthHelper.put_session_user(user.id)
|> after_create_authorization(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, view_module: OAuthView})
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, :user_is_not_an_admin] 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 of 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
after_token_exchange(conn, %{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.get_or_exchange_token(auth, app, user) do
after_token_exchange(conn, %{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
after_token_exchange(conn, %{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
after_token_exchange(conn, %{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)
def after_token_exchange(%Plug.Conn{} = conn, %{token: token} = view_params) do
conn
|> AuthHelper.put_session_token(token.token)
|> AuthHelper.put_session_user(token.user_id)
|> json(OAuthView.render("token.json", view_params))
end
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}) do
with {:ok, %Token{} = oauth_token} <- Token.get_by_token(token),
{:ok, oauth_token} <- RevokeToken.revoke(oauth_token) do
conn =
with session_token = AuthHelper.get_session_token(conn),
%Token{token: ^session_token} <- oauth_token do
AuthHelper.delete_session_token(conn)
else
_ -> conn
end
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!()
# Handing the request to Ueberauth
conn
|> put_resp_cookie(@state_cookie_name, state)
|> redirect(to: ~p"/oauth/#{provider}")
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(conn, params)
messages = for e <- Map.get(failure, :errors, []), do: e.message
message = Enum.join(messages, "; ")
error_message = dgettext("errors", "Failed to authenticate: %{message}.", message: message)
if params["redirect_uri"] do
conn
|> put_flash(
:error,
error_message
)
|> redirect(external: redirect_uri(conn, params["redirect_uri"]))
else
send_resp(conn, :bad_request, error_message)
end
end
def callback(%Plug.Conn{} = conn, params) do
params = callback_params(conn, 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(%Plug.Conn{} = conn, params) do
fetch_cookies(conn)
Map.merge(params, Jason.decode!(Map.get(conn.req_cookies, @state_cookie_name, "{}")))
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_join(changeset.errors, "; ", fn {field, {error, _}} ->
"#{field} #{error}"
end)
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)},
requested_scopes <- Scopes.filter_admin_scopes(requested_scopes, user),
{:ok, scopes} <- validate_scopes(user, 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(_, "."), do: url(~p"/web/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(User.t(), App.t(), map() | list()) ::
{:ok, list()} | {:error, :missing_scopes | :unsupported_scopes}
defp validate_scopes(%User{} = user, %App{} = app, params) when is_map(params) do
requested_scopes = Scopes.fetch_scopes(params, app.scopes)
validate_scopes(user, app, requested_scopes)
end
defp validate_scopes(%User{} = user, %App{} = app, requested_scopes)
when is_list(requested_scopes) do
Scopes.validate(requested_scopes, app.scopes, user)
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