import logging import urlparse from decimal import Decimal from zope.interface import implements from twisted.web import server, resource from twisted.internet import defer from twisted.python.failure import Failure from txjsonrpc import jsonrpclib from lbrynet.core.Error import InvalidAuthenticationToken, InvalidHeaderError, SubhandlerError from lbrynet.conf import settings from lbrynet.core import log_support from lbrynet.lbrynet_daemon.auth.util import APIKey, get_auth_message from lbrynet.lbrynet_daemon.auth.client import LBRY_SECRET log = logging.getLogger(__name__) def default_decimal(obj): if isinstance(obj, Decimal): return float(obj) class JSONRPCException(Exception): def __init__(self, err, code): self.faultCode = code self.err = err @property def faultString(self): return self.err.getTraceback() class AuthorizedBase(object): def __init__(self): self.authorized_functions = [] self.subhandlers = [] self.callable_methods = {} for methodname in dir(self): if methodname.startswith("jsonrpc_"): method = getattr(self, methodname) self.callable_methods.update({methodname.split("jsonrpc_")[1]: method}) if hasattr(method, '_auth_required'): self.authorized_functions.append(methodname.split("jsonrpc_")[1]) elif not methodname.startswith("__"): method = getattr(self, methodname) if hasattr(method, '_subhandler'): self.subhandlers.append(method) @staticmethod def auth_required(f): f._auth_required = True return f @staticmethod def subhandler(f): f._subhandler = True return f class AuthJSONRPCServer(AuthorizedBase): """Authorized JSONRPC server used as the base class for the LBRY API API methods are named with a leading "jsonrpc_" Decorators: @AuthJSONRPCServer.auth_required: this requires the client include a valid hmac authentication token in their request @AuthJSONRPCServer.subhandler: include the tagged method in the processing of requests, to allow inheriting classes to modify request handling. Tagged methods will be passed the request object, and return True when finished to indicate success Attributes: allowed_during_startup (list): list of api methods that are callable before the server has finished startup sessions (dict): dictionary of active session_id: lbrynet.lbrynet_daemon.auth.util.APIKey values authorized_functions (list): list of api methods that require authentication subhandlers (list): list of subhandlers callable_methods (dict): dictionary of api_callable_name: method values """ implements(resource.IResource) isLeaf = True OK = 200 UNAUTHORIZED = 401 NOT_FOUND = 8001 FAILURE = 8002 def __init__(self, use_authentication=settings.use_auth_http): AuthorizedBase.__init__(self) self._use_authentication = use_authentication self.announced_startup = False self.allowed_during_startup = [] self.sessions = {} def setup(self): return NotImplementedError() def _render_error(self, failure, request, version=jsonrpclib.VERSION_1, response_code=FAILURE): err = JSONRPCException(Failure(failure), response_code) fault = jsonrpclib.dumps(err, version=version) self._set_headers(request, fault) if response_code != AuthJSONRPCServer.FAILURE: request.setResponseCode(response_code) request.write(fault) request.finish() def _log_and_render_error(self, failure, request, message=None, **kwargs): msg = message or "API Failure: %s" log_support.failure(Failure(failure), log, msg) self._render_error(failure, request, **kwargs) def render(self, request): notify_finish = request.notifyFinish() assert self._check_headers(request), InvalidHeaderError session = request.getSession() session_id = session.uid 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(self.OK) self._set_headers(request, message, True) self._render_message(request, message) return server.NOT_DONE_YET session.touch() request.content.seek(0, 0) content = request.content.read() try: parsed = jsonrpclib.loads(content) except ValueError as err: log.warning("Unable to decode request json") self._render_error(err, request) return server.NOT_DONE_YET function_name = parsed.get('method') args = parsed.get('params') id = parsed.get('id') token = parsed.pop('hmac', None) version = self._get_jsonrpc_version(parsed.get('jsonrpc'), id) try: self._run_subhandlers(request) except SubhandlerError as err: self._render_error(err, request, version) return server.NOT_DONE_YET reply_with_next_secret = False if self._use_authentication: if function_name in self.authorized_functions: try: self._verify_token(session_id, parsed, token) except InvalidAuthenticationToken as err: log.warning("API validation failed") self._render_error( err, request, version=version, response_code=AuthJSONRPCServer.UNAUTHORIZED) return server.NOT_DONE_YET self._update_session_secret(session_id) reply_with_next_secret = True try: function = self._get_jsonrpc_method(function_name) except AttributeError as err: log.warning("Unknown method: %s", function_name) self._render_error(err, request, version) return server.NOT_DONE_YET if args == [{}]: d = defer.maybeDeferred(function) else: d = defer.maybeDeferred(function, *args) # cancel the response if the connection is broken notify_finish.addErrback(self._response_failed, d) d.addCallback(self._callback_render, request, version, reply_with_next_secret) d.addErrback(self._log_and_render_error, request, version=version) 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("Register 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 _response_failed(self, err, call): log.debug(err.getTraceback()) def _set_headers(self, request, data, update_secret=False): if settings.allowed_origin: request.setHeader("Access-Control-Allow-Origin", settings.allowed_origin) request.setHeader("Content-Type", "text/json") 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) def _render_message(self, request, message): request.write(message) request.finish() 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 settings.API_INTERFACE == '0.0.0.0': return True server, port = self.get_server_port(source) return ( server == settings.API_INTERFACE and port == settings.api_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 _check_function_path(self, function_path): if function_path not in self.callable_methods: log.warning("Unknown method: %s", function_path) return False if not self.announced_startup: if function_path not in self.allowed_during_startup: log.warning("Cannot call %s during startup", function_path) return False return True def _get_jsonrpc_method(self, function_path): if not self._check_function_path(function_path): raise AttributeError(function_path) return self.callable_methods.get(function_path) def _initialize_session(self, session_id): if not self.sessions.get(session_id, False): self._register_user_session(session_id) return True return False def _verify_token(self, session_id, message, token): to_auth = get_auth_message(message) api_key = self.sessions.get(session_id) assert api_key.compare_hmac(to_auth, token), InvalidAuthenticationToken def _update_session_secret(self, session_id): # log.info("Generating new token for next request") self.sessions.update({session_id: APIKey.new(name=session_id)}) def _get_jsonrpc_version(self, version=None, id=None): if version: version_for_return = int(float(version)) elif id and not version: version_for_return = jsonrpclib.VERSION_1 else: version_for_return = jsonrpclib.VERSION_PRE1 return version_for_return def _run_subhandlers(self, request): for handler in self.subhandlers: if not handler(request): raise SubhandlerError("Subhandler error processing request: %s", request) def _callback_render(self, result, request, version, auth_required=False): result_for_return = result if not isinstance(result, dict) else result['result'] if version == jsonrpclib.VERSION_PRE1: if not isinstance(result, jsonrpclib.Fault): result_for_return = (result_for_return,) # Convert the result (python) to JSON-RPC try: encoded_message = jsonrpclib.dumps( result_for_return, version=version, default=default_decimal) self._set_headers(request, encoded_message, auth_required) self._render_message(request, encoded_message) except Exception as err: msg = "Failed to render API response: %s" self._log_and_render_error(err, request, message=msg, version=version) def _render_response(self, result, code): return defer.succeed({'result': result, 'code': code})