import logging from six.moves.urllib import parse as urlparse import json import inspect import signal from decimal import Decimal from functools import wraps from twisted.web import server from twisted.internet import defer from twisted.python.failure import Failure from twisted.internet.error import ConnectionDone, ConnectionLost from txjsonrpc import jsonrpclib from traceback import format_exc from lbrynet import conf, analytics from lbrynet.core.Error import InvalidAuthenticationToken from lbrynet.core import utils from lbrynet.core.Error import ComponentsNotStarted, ComponentStartConditionNotMet from lbrynet.core.looping_call_manager import LoopingCallManager from lbrynet.daemon.ComponentManager import ComponentManager from .util import APIKey, get_auth_message, LBRY_SECRET from .undecorated import undecorated from .factory import AuthJSONRPCResource log = logging.getLogger(__name__) EMPTY_PARAMS = [{}] class JSONRPCError: # http://www.jsonrpc.org/specification#error_object CODE_PARSE_ERROR = -32700 # Invalid JSON. Error while parsing the JSON text. CODE_INVALID_REQUEST = -32600 # The JSON sent is not a valid Request object. CODE_METHOD_NOT_FOUND = -32601 # The method does not exist / is not available. CODE_INVALID_PARAMS = -32602 # Invalid method parameter(s). CODE_INTERNAL_ERROR = -32603 # Internal JSON-RPC error (I think this is like a 500?) CODE_APPLICATION_ERROR = -32500 # Generic error with our app?? CODE_AUTHENTICATION_ERROR = -32501 # Authentication failed MESSAGES = { CODE_PARSE_ERROR: "Parse Error. Data is not valid JSON.", CODE_INVALID_REQUEST: "JSON data is not a valid Request", CODE_METHOD_NOT_FOUND: "Method Not Found", CODE_INVALID_PARAMS: "Invalid Params", CODE_INTERNAL_ERROR: "Internal Error", CODE_AUTHENTICATION_ERROR: "Authentication Failed", } HTTP_CODES = { CODE_INVALID_REQUEST: 400, CODE_PARSE_ERROR: 400, CODE_INVALID_PARAMS: 400, CODE_METHOD_NOT_FOUND: 404, CODE_INTERNAL_ERROR: 500, CODE_APPLICATION_ERROR: 500, CODE_AUTHENTICATION_ERROR: 401, } def __init__(self, message, code=CODE_APPLICATION_ERROR, traceback=None, data=None): assert isinstance(code, int), "'code' must be an int" assert (data is None or isinstance(data, dict)), "'data' must be None or a dict" self.code = code if message is None: message = self.MESSAGES[code] if code in self.MESSAGES else "API Error" self.message = message self.data = {} if data is None else data self.traceback = [] if traceback is not None: trace_lines = traceback.split("\n") for i, t in enumerate(trace_lines): if "--- ---" in t: if len(trace_lines) > i + 1: self.traceback = [j for j in trace_lines[i+1:] if j] break def to_dict(self): return { 'code': self.code, 'message': self.message, 'data': self.traceback } @classmethod def create_from_exception(cls, exception, code=CODE_APPLICATION_ERROR, traceback=None): return cls(exception.message, code=code, traceback=traceback) def default_decimal(obj): if isinstance(obj, Decimal): return float(obj) class UnknownAPIMethodError(Exception): pass def trap(err, *to_trap): err.trap(*to_trap) def jsonrpc_dumps_pretty(obj, **kwargs): try: id_ = kwargs.pop("id") except KeyError: id_ = None if isinstance(obj, JSONRPCError): data = {"jsonrpc": "2.0", "error": obj.to_dict(), "id": id_} else: data = {"jsonrpc": "2.0", "result": obj, "id": id_} return json.dumps(data, cls=jsonrpclib.JSONRPCEncoder, sort_keys=True, indent=2, separators=(',', ': '), **kwargs) + "\n" class JSONRPCServerType(type): def __new__(mcs, name, bases, newattrs): klass = type.__new__(mcs, name, bases, newattrs) klass.callable_methods = {} klass.deprecated_methods = {} for methodname in dir(klass): if methodname.startswith("jsonrpc_"): method = getattr(klass, methodname) if not hasattr(method, '_deprecated'): klass.callable_methods.update({methodname.split("jsonrpc_")[1]: method}) else: klass.deprecated_methods.update({methodname.split("jsonrpc_")[1]: method}) return klass class AuthorizedBase(metaclass=JSONRPCServerType): @staticmethod def deprecated(new_command=None): def _deprecated_wrapper(f): f._new_command = new_command f._deprecated = True return f return _deprecated_wrapper @staticmethod def requires(*components, **conditions): if conditions and ["conditions"] != list(conditions.keys()): raise SyntaxError("invalid conditions argument") condition_names = conditions.get("conditions", []) def _wrap(fn): @defer.inlineCallbacks @wraps(fn) def _inner(*args, **kwargs): component_manager = args[0].component_manager for condition_name in condition_names: condition_result, err_msg = yield component_manager.evaluate_condition(condition_name) if not condition_result: raise ComponentStartConditionNotMet(err_msg) if not component_manager.all_components_running(*components): raise ComponentsNotStarted("the following required components have not yet started: " "%s" % json.dumps(components)) result = yield fn(*args, **kwargs) defer.returnValue(result) return _inner return _wrap class AuthJSONRPCServer(AuthorizedBase): """ Authorized JSONRPC server used as the base class for the LBRY API API methods are named with a leading "jsonrpc_" Attributes: sessions (dict): (dict): {: } callable_methods (dict): {: } Authentication: If use_authentication is true, basic HTTP and HMAC authentication will be used for all requests and the service url will require a username and password. To start an authenticated session a client sends an HTTP POST to :@:. If accepted, the server replies with a TWISTED_SESSION cookie containing a session id and the message "OK". The client initializes their shared secret for hmac to be the b64 encoded sha256 of their session id. To send an authenticated request a client sends an HTTP POST to the auth api url with the TWISTED_SESSION cookie and includes a hmac token in the message using the previously set shared secret. If the token is valid the server will randomize the shared secret and return the new value under the LBRY_SECRET header, which the client uses to generate the token for their next request. """ #implements(resource.IResource) isLeaf = True allowed_during_startup = [] component_attributes = {} def __init__(self, analytics_manager=None, component_manager=None, use_authentication=None, to_skip=None, looping_calls=None, reactor=None): if not reactor: from twisted.internet import reactor self.analytics_manager = analytics_manager or analytics.Manager.new_instance() self.component_manager = component_manager or ComponentManager( analytics_manager=self.analytics_manager, skip_components=to_skip or [], reactor=reactor ) self.looping_call_manager = LoopingCallManager({n: lc for n, (lc, t) in (looping_calls or {}).items()}) self._looping_call_times = {n: t for n, (lc, t) in (looping_calls or {}).items()} self._use_authentication = use_authentication or conf.settings['use_auth_http'] self._component_setup_deferred = None self.announced_startup = False self.sessions = {} @defer.inlineCallbacks def start_listening(self): from twisted.internet import reactor, error as tx_error try: reactor.listenTCP( conf.settings['api_port'], self.get_server_factory(), interface=conf.settings['api_host'] ) log.info("lbrynet API listening on TCP %s:%i", conf.settings['api_host'], conf.settings['api_port']) yield self.setup() self.analytics_manager.send_server_startup_success() except tx_error.CannotListenError: log.error('lbrynet API failed to bind TCP %s:%i for listening', conf.settings['api_host'], conf.settings['api_port']) reactor.fireSystemEvent("shutdown") except defer.CancelledError: log.info("shutting down before finished starting") reactor.fireSystemEvent("shutdown") except Exception as err: self.analytics_manager.send_server_startup_error(str(err)) log.exception('Failed to start lbrynet-daemon') reactor.fireSystemEvent("shutdown") def setup(self): from twisted.internet import reactor reactor.addSystemEventTrigger('before', 'shutdown', self._shutdown) if not self.analytics_manager.is_started: self.analytics_manager.start() for lc_name, lc_time in self._looping_call_times.items(): self.looping_call_manager.start(lc_name, lc_time) def update_attribute(setup_result, component): setattr(self, self.component_attributes[component.component_name], component.component) kwargs = {component: update_attribute for component in self.component_attributes.keys()} self._component_setup_deferred = self.component_manager.setup(**kwargs) return self._component_setup_deferred @staticmethod def _already_shutting_down(sig_num, frame): log.info("Already shutting down") def _shutdown(self): # ignore INT/TERM signals once shutdown has started signal.signal(signal.SIGINT, self._already_shutting_down) signal.signal(signal.SIGTERM, self._already_shutting_down) self.looping_call_manager.shutdown() if self.analytics_manager: self.analytics_manager.shutdown() try: self._component_setup_deferred.cancel() except (AttributeError, defer.CancelledError): pass if self.component_manager is not None: d = self.component_manager.stop() d.addErrback(log.fail(), 'Failure while shutting down') else: d = defer.succeed(None) return d def get_server_factory(self): return AuthJSONRPCResource(self).getServerFactory() def _set_headers(self, request, data, update_secret=False): if conf.settings['allowed_origin']: request.setHeader("Access-Control-Allow-Origin", conf.settings['allowed_origin']) request.setHeader("Content-Type", "application/json") request.setHeader("Accept", "application/json-rpc") request.setHeader("Content-Length", str(len(data))) if update_secret: session_id = request.getSession().uid request.setHeader(LBRY_SECRET, self.sessions.get(session_id).secret) @staticmethod def _render_message(request, message): request.write(message) request.finish() def _render_error(self, failure, request, id_): if isinstance(failure, JSONRPCError): error = failure elif isinstance(failure, Failure): # maybe failure is JSONRPCError wrapped in a twisted Failure error = failure.check(JSONRPCError) if error is None: # maybe its a twisted Failure with another type of error error = JSONRPCError(failure.getErrorMessage() or failure.type.__name__, traceback=failure.getTraceback()) if not failure.check(ComponentsNotStarted, ComponentStartConditionNotMet): log.warning("error processing api request: %s\ntraceback: %s", error.message, "\n".join(error.traceback)) else: # last resort, just cast it as a string error = JSONRPCError(str(failure)) response_content = jsonrpc_dumps_pretty(error, id=id_) self._set_headers(request, response_content) request.setResponseCode(200) self._render_message(request, response_content) @staticmethod def _handle_dropped_request(result, d, function_name): if not d.called: log.warning("Cancelling dropped api request %s", function_name) d.cancel() def render(self, request): try: return self._render(request) except BaseException as e: log.error(e) error = JSONRPCError.create_from_exception(e, traceback=format_exc()) self._render_error(error, request, None) return server.NOT_DONE_YET def _render(self, request): time_in = utils.now() # if not self._check_headers(request): # self._render_error(Failure(InvalidHeaderError()), request, None) # return server.NOT_DONE_YET session = request.getSession() session_id = session.uid finished_deferred = request.notifyFinish() if self._use_authentication: # if this is a new session, send a new secret and set the expiration # otherwise, session.touch() if self._initialize_session(session_id): def expire_session(): self._unregister_user_session(session_id) session.startCheckingExpiration() session.notifyOnExpire(expire_session) message = "OK" request.setResponseCode(200) self._set_headers(request, message, True) self._render_message(request, message) return server.NOT_DONE_YET else: session.touch() request.content.seek(0, 0) content = request.content.read() try: parsed = jsonrpclib.loads(content) except ValueError: log.warning("Unable to decode request json") self._render_error(JSONRPCError(None, JSONRPCError.CODE_PARSE_ERROR), request, None) return server.NOT_DONE_YET request_id = None try: function_name = parsed.get('method') args = parsed.get('params', {}) request_id = parsed.get('id', None) token = parsed.pop('hmac', None) except AttributeError as err: log.warning(err) self._render_error( JSONRPCError(None, code=JSONRPCError.CODE_INVALID_REQUEST), request, request_id ) return server.NOT_DONE_YET reply_with_next_secret = False if self._use_authentication: try: self._verify_token(session_id, parsed, token) except InvalidAuthenticationToken as err: log.warning("API validation failed") self._render_error( JSONRPCError.create_from_exception( err, code=JSONRPCError.CODE_AUTHENTICATION_ERROR, traceback=format_exc() ), request, request_id ) return server.NOT_DONE_YET request.addCookie("TWISTED_SESSION", session_id) self._update_session_secret(session_id) reply_with_next_secret = True try: fn = self._get_jsonrpc_method(function_name) except UnknownAPIMethodError as err: log.warning('Failed to get function %s: %s', function_name, err) self._render_error( JSONRPCError(None, JSONRPCError.CODE_METHOD_NOT_FOUND), request, request_id ) return server.NOT_DONE_YET if args in (EMPTY_PARAMS, []): _args, _kwargs = (), {} elif isinstance(args, dict): _args, _kwargs = (), args elif len(args) == 1 and isinstance(args[0], dict): # TODO: this is for backwards compatibility. Remove this once API and UI are updated # TODO: also delete EMPTY_PARAMS then _args, _kwargs = (), args[0] elif len(args) == 2 and isinstance(args[0], list) and isinstance(args[1], dict): _args, _kwargs = args else: raise ValueError('invalid args format') params_error, erroneous_params = self._check_params(fn, _args, _kwargs) if params_error is not None: params_error_message = '{} for {} command: {}'.format( params_error, function_name, ', '.join(erroneous_params) ) log.warning(params_error_message) self._render_error( JSONRPCError(params_error_message, code=JSONRPCError.CODE_INVALID_PARAMS), request, request_id ) return server.NOT_DONE_YET d = defer.maybeDeferred(fn, self, *_args, **_kwargs) # finished_deferred will callback when the request is finished # and errback if something went wrong. If the errback is # called, cancel the deferred stack. This is to prevent # request.finish() from being called on a closed request. finished_deferred.addErrback(self._handle_dropped_request, d, function_name) d.addCallback(self._callback_render, request, request_id, reply_with_next_secret) d.addErrback(trap, ConnectionDone, ConnectionLost, defer.CancelledError) d.addErrback(self._render_error, request, request_id) d.addBoth(lambda _: log.debug("%s took %f", function_name, (utils.now() - time_in).total_seconds())) return server.NOT_DONE_YET def _register_user_session(self, session_id): """ Add or update a HMAC secret for a session @param session_id: @return: secret """ log.info("Started new api session") token = APIKey.new(seed=session_id) self.sessions.update({session_id: token}) def _unregister_user_session(self, session_id): log.info("Unregister API session") del self.sessions[session_id] def _check_headers(self, request): return ( self._check_header_source(request, 'Origin') and self._check_header_source(request, 'Referer') ) def _check_header_source(self, request, header): """Check if the source of the request is allowed based on the header value.""" source = request.getHeader(header) if not self._check_source_of_request(source): log.warning("Attempted api call from invalid %s: %s", header, source) return False return True def _check_source_of_request(self, source): if source is None: return True if conf.settings['api_host'] == '0.0.0.0': return True server, port = self.get_server_port(source) return self._check_server_port(server, port) def _check_server_port(self, server, port): api = (conf.settings['api_host'], conf.settings['api_port']) return (server, port) == api or self._is_from_allowed_origin(server, port) def _is_from_allowed_origin(self, server, port): allowed_origin = conf.settings['allowed_origin'] if not allowed_origin: return False if allowed_origin == '*': return True allowed_server, allowed_port = self.get_server_port(allowed_origin) return (allowed_server, allowed_port) == (server, port) def get_server_port(self, origin): parsed = urlparse.urlparse(origin) server_port = parsed.netloc.split(':') assert len(server_port) <= 2 if len(server_port) == 2: return server_port[0], int(server_port[1]) else: return server_port[0], 80 def _verify_method_is_callable(self, function_path): if function_path not in self.callable_methods: raise UnknownAPIMethodError(function_path) def _get_jsonrpc_method(self, function_path): if function_path in self.deprecated_methods: new_command = self.deprecated_methods[function_path]._new_command log.warning('API function \"%s\" is deprecated, please update to use \"%s\"', function_path, new_command) function_path = new_command self._verify_method_is_callable(function_path) return self.callable_methods.get(function_path) @staticmethod def _check_params(function, args_tup, args_dict): argspec = inspect.getfullargspec(undecorated(function)) num_optional_params = 0 if argspec.defaults is None else len(argspec.defaults) duplicate_params = [ duplicate_param for duplicate_param in argspec.args[1:len(args_tup) + 1] if duplicate_param in args_dict ] if duplicate_params: return 'Duplicate parameters', duplicate_params missing_required_params = [ required_param for required_param in argspec.args[len(args_tup)+1:-num_optional_params] if required_param not in args_dict ] if len(missing_required_params): return 'Missing required parameters', missing_required_params extraneous_params = [] if argspec.varkw is not None else [ extra_param for extra_param in args_dict if extra_param not in argspec.args[1:] ] if len(extraneous_params): return 'Extraneous parameters', extraneous_params return None, None def _initialize_session(self, session_id): if not self.sessions.get(session_id): self._register_user_session(session_id) return True return False def _verify_token(self, session_id, message, token): if token is None: raise InvalidAuthenticationToken('Authentication token not found') to_auth = get_auth_message(message) api_key = self.sessions.get(session_id) if not api_key.compare_hmac(to_auth, token): raise InvalidAuthenticationToken('Invalid authentication token') def _update_session_secret(self, session_id): self.sessions.update({session_id: APIKey.new(name=session_id)}) def _callback_render(self, result, request, id_, auth_required=False): try: encoded_message = jsonrpc_dumps_pretty(result, id=id_, default=default_decimal).encode() request.setResponseCode(200) self._set_headers(request, encoded_message, auth_required) self._render_message(request, encoded_message) except Exception as err: log.exception("Failed to render API response: %s", result) self._render_error(err, request, id_) @staticmethod def _render_response(result): return defer.succeed(result)