""" This module provides more sophisticated flow tracking. These match requests with their responses, and provide filtering and interception facilities. """ import hashlib, Cookie, cookielib, copy, re, urlparse, threading import time, urllib import types import tnetstring, filt, script, utils, encoding, proxy from email.utils import parsedate_tz, formatdate, mktime_tz from netlib import odict, http, certutils, wsgi from .proxy import ClientConnection, ServerConnection import controller, version, protocol, stateobject import app HDR_FORM_URLENCODED = "application/x-www-form-urlencoded" CONTENT_MISSING = 0 ODict = odict.ODict ODictCaseless = odict.ODictCaseless class BackreferenceMixin(object): """ If an attribute from the _backrefattr tuple is set, this mixin sets a reference back on the attribute object. Example: e = Error() f = Flow() f.error = e assert f is e.flow """ _backrefattr = tuple() def __setattr__(self, key, value): super(BackreferenceMixin, self).__setattr__(key, value) if key in self._backrefattr and value is not None: setattr(value, self._backrefname, self) class Error(stateobject.SimpleStateObject): """ An Error. This is distinct from an HTTP error response (say, a code 500), which is represented by a normal Response object. This class is responsible for indicating errors that fall outside of normal HTTP communications, like interrupted connections, timeouts, protocol errors. Exposes the following attributes: flow: Flow object msg: Message describing the error timestamp: Seconds since the epoch """ def __init__(self, msg, timestamp=None): """ @type msg: str @type timestamp: float """ self.msg = msg self.timestamp = timestamp or utils.timestamp() _stateobject_attributes = dict( msg=str, timestamp=float ) @classmethod def _from_state(cls, state): f = cls(None) # the default implementation assumes an empty constructor. Override accordingly. f._load_state(state) return f def copy(self): c = copy.copy(self) return c class Flow(stateobject.SimpleStateObject, BackreferenceMixin): def __init__(self, conntype, client_conn, server_conn): self.conntype = conntype self.client_conn = client_conn self.server_conn = server_conn self.error = None _backrefattr = ("error",) _backrefname = "flow" _stateobject_attributes = dict( error=Error, client_conn=ClientConnection, server_conn=ServerConnection, conntype=str ) def _get_state(self): d = super(Flow, self)._get_state() d.update(version=version.IVERSION) return d @classmethod def _from_state(cls, state): f = cls(None, None, None) f._load_state(state) return f def copy(self): f = copy.copy(self) if self.error: f.error = self.error.copy() return f def modified(self): """ Has this Flow been modified? """ if self._backup: return self._backup != self._get_state() else: return False def backup(self, force=False): """ Save a backup of this Flow, which can be reverted to using a call to .revert(). """ if not self._backup: self._backup = self._get_state() def revert(self): """ Revert to the last backed up state. """ if self._backup: self._load_state(self._backup) self._backup = None class AppRegistry: def __init__(self): self.apps = {} def add(self, app, domain, port): """ Add a WSGI app to the registry, to be served for requests to the specified domain, on the specified port. """ self.apps[(domain, port)] = wsgi.WSGIAdaptor(app, domain, port, version.NAMEVERSION) def get(self, request): """ Returns an WSGIAdaptor instance if request matches an app, or None. """ if (request.host, request.port) in self.apps: return self.apps[(request.host, request.port)] if "host" in request.headers: host = request.headers["host"][0] return self.apps.get((host, request.port), None) class ReplaceHooks: def __init__(self): self.lst = [] def set(self, r): self.clear() for i in r: self.add(*i) def add(self, fpatt, rex, s): """ add a replacement hook. fpatt: a string specifying a filter pattern. rex: a regular expression. s: the replacement string returns true if hook was added, false if the pattern could not be parsed. """ cpatt = filt.parse(fpatt) if not cpatt: return False try: re.compile(rex) except re.error: return False self.lst.append((fpatt, rex, s, cpatt)) return True def get_specs(self): """ Retrieve the hook specifcations. Returns a list of (fpatt, rex, s) tuples. """ return [i[:3] for i in self.lst] def count(self): return len(self.lst) def run(self, f): for _, rex, s, cpatt in self.lst: if cpatt(f): if f.response: f.response.replace(rex, s) else: f.request.replace(rex, s) def clear(self): self.lst = [] class SetHeaders: def __init__(self): self.lst = [] def set(self, r): self.clear() for i in r: self.add(*i) def add(self, fpatt, header, value): """ Add a set header hook. fpatt: String specifying a filter pattern. header: Header name. value: Header value string Returns True if hook was added, False if the pattern could not be parsed. """ cpatt = filt.parse(fpatt) if not cpatt: return False self.lst.append((fpatt, header, value, cpatt)) return True def get_specs(self): """ Retrieve the hook specifcations. Returns a list of (fpatt, rex, s) tuples. """ return [i[:3] for i in self.lst] def count(self): return len(self.lst) def clear(self): self.lst = [] def run(self, f): for _, header, value, cpatt in self.lst: if cpatt(f): if f.response: del f.response.headers[header] else: del f.request.headers[header] for _, header, value, cpatt in self.lst: if cpatt(f): if f.response: f.response.headers.add(header, value) else: f.request.headers.add(header, value) class ClientPlaybackState: def __init__(self, flows, exit): self.flows, self.exit = flows, exit self.current = None def count(self): return len(self.flows) def done(self): if len(self.flows) == 0 and not self.current: return True return False def clear(self, flow): """ A request has returned in some way - if this is the one we're servicing, go to the next flow. """ if flow is self.current: self.current = None def tick(self, master, testing=False): """ testing: Disables actual replay for testing. """ if self.flows and not self.current: n = self.flows.pop(0) n.request.reply = controller.DummyReply() n.request.client_conn = None self.current = master.handle_request(n.request) if not testing and not self.current.response: master.replay_request(self.current) # pragma: no cover elif self.current.response: master.handle_response(self.current.response) class ServerPlaybackState: def __init__(self, headers, flows, exit, nopop): """ headers: Case-insensitive list of request headers that should be included in request-response matching. """ self.headers, self.exit, self.nopop = headers, exit, nopop self.fmap = {} for i in flows: if i.response: l = self.fmap.setdefault(self._hash(i), []) l.append(i) def count(self): return sum(len(i) for i in self.fmap.values()) def _hash(self, flow): """ Calculates a loose hash of the flow request. """ r = flow.request key = [ str(r.host), str(r.port), str(r.scheme), str(r.method), str(r.path), str(r.content), ] if self.headers: hdrs = [] for i in self.headers: v = r.headers[i] # Slightly subtle: we need to convert everything to strings # to prevent a mismatch between unicode/non-unicode. v = [str(x) for x in v] hdrs.append((i, v)) key.append(repr(hdrs)) return hashlib.sha256(repr(key)).digest() def next_flow(self, request): """ Returns the next flow object, or None if no matching flow was found. """ l = self.fmap.get(self._hash(request)) if not l: return None if self.nopop: return l[0] else: return l.pop(0) class StickyCookieState: def __init__(self, flt): """ flt: Compiled filter. """ self.jar = {} self.flt = flt def ckey(self, m, f): """ Returns a (domain, port, path) tuple. """ return ( m["domain"] or f.request.host, f.request.port, m["path"] or "/" ) def domain_match(self, a, b): if cookielib.domain_match(a, b): return True elif cookielib.domain_match(a, b.strip(".")): return True return False def handle_response(self, f): for i in f.response.headers["set-cookie"]: # FIXME: We now know that Cookie.py screws up some cookies with # valid RFC 822/1123 datetime specifications for expiry. Sigh. c = Cookie.SimpleCookie(str(i)) m = c.values()[0] k = self.ckey(m, f) if self.domain_match(f.request.host, k[0]): self.jar[self.ckey(m, f)] = m def handle_request(self, f): l = [] if f.match(self.flt): for i in self.jar.keys(): match = [ self.domain_match(f.request.host, i[0]), f.request.port == i[1], f.request.path.startswith(i[2]) ] if all(match): l.append(self.jar[i].output(header="").strip()) if l: f.request.stickycookie = True f.request.headers["cookie"] = l class StickyAuthState: def __init__(self, flt): """ flt: Compiled filter. """ self.flt = flt self.hosts = {} def handle_request(self, f): if "authorization" in f.request.headers: self.hosts[f.request.host] = f.request.headers["authorization"] elif f.match(self.flt): if f.request.host in self.hosts: f.request.headers["authorization"] = self.hosts[f.request.host] class State(object): def __init__(self): self._flow_list = [] self.view = [] # These are compiled filt expressions: self._limit = None self.intercept = None self._limit_txt = None @property def limit_txt(self): return self._limit_txt def flow_count(self): return len(self._flow_list) def index(self, f): return self._flow_list.index(f) def active_flow_count(self): c = 0 for i in self._flow_list: if not i.response and not i.error: c += 1 return c def add_request(self, req): """ Add a request to the state. Returns the matching flow. """ f = req.flow self._flow_list.append(f) if f.match(self._limit): self.view.append(f) return f def add_response(self, resp): """ Add a response to the state. Returns the matching flow. """ f = resp.flow if not f: return False if f.match(self._limit) and not f in self.view: self.view.append(f) return f def add_error(self, err): """ Add an error response to the state. Returns the matching flow, or None if there isn't one. """ f = err.flow if not f: return None if f.match(self._limit) and not f in self.view: self.view.append(f) return f def load_flows(self, flows): self._flow_list.extend(flows) self.recalculate_view() def set_limit(self, txt): if txt: f = filt.parse(txt) if not f: return "Invalid filter expression." self._limit = f self._limit_txt = txt else: self._limit = None self._limit_txt = None self.recalculate_view() def set_intercept(self, txt): if txt: f = filt.parse(txt) if not f: return "Invalid filter expression." self.intercept = f self.intercept_txt = txt else: self.intercept = None self.intercept_txt = None def recalculate_view(self): if self._limit: self.view = [i for i in self._flow_list if i.match(self._limit)] else: self.view = self._flow_list[:] def delete_flow(self, f): self._flow_list.remove(f) if f in self.view: self.view.remove(f) return True def clear(self): for i in self._flow_list[:]: self.delete_flow(i) def accept_all(self): for i in self._flow_list[:]: i.accept_intercept() def revert(self, f): f.revert() def killall(self, master): for i in self._flow_list: i.kill(master) class FlowMaster(controller.Master): def __init__(self, server, state): controller.Master.__init__(self, server) self.state = state self.server_playback = None self.client_playback = None self.kill_nonreplay = False self.scripts = [] self.pause_scripts = False self.stickycookie_state = False self.stickycookie_txt = None self.stickyauth_state = False self.stickyauth_txt = None self.anticache = False self.anticomp = False self.refresh_server_playback = False self.replacehooks = ReplaceHooks() self.setheaders = SetHeaders() self.stream = None self.apps = AppRegistry() def start_app(self, host, port, external): if not external: self.apps.add( app.mapp, host, port ) else: threading.Thread(target=app.mapp.run,kwargs={ "use_reloader": False, "host": host, "port": port}).start() def add_event(self, e, level="info"): """ level: info, error """ pass def unload_scripts(self): for s in self.scripts[:]: s.unload() self.scripts.remove(s) def load_script(self, command): """ Loads a script. Returns an error description if something went wrong. """ try: s = script.Script(command, self) except script.ScriptError, v: return v.args[0] self.scripts.append(s) def run_single_script_hook(self, script, name, *args, **kwargs): if script and not self.pause_scripts: ret = script.run(name, *args, **kwargs) if not ret[0] and ret[1]: e = "Script error:\n" + ret[1][1] self.add_event(e, "error") def run_script_hook(self, name, *args, **kwargs): for script in self.scripts: self.run_single_script_hook(script, name, *args, **kwargs) def set_stickycookie(self, txt): if txt: flt = filt.parse(txt) if not flt: return "Invalid filter expression." self.stickycookie_state = StickyCookieState(flt) self.stickycookie_txt = txt else: self.stickycookie_state = None self.stickycookie_txt = None def set_stickyauth(self, txt): if txt: flt = filt.parse(txt) if not flt: return "Invalid filter expression." self.stickyauth_state = StickyAuthState(flt) self.stickyauth_txt = txt else: self.stickyauth_state = None self.stickyauth_txt = None def start_client_playback(self, flows, exit): """ flows: List of flows. """ self.client_playback = ClientPlaybackState(flows, exit) def stop_client_playback(self): self.client_playback = None def start_server_playback(self, flows, kill, headers, exit, nopop): """ flows: List of flows. kill: Boolean, should we kill requests not part of the replay? """ self.server_playback = ServerPlaybackState(headers, flows, exit, nopop) self.kill_nonreplay = kill def stop_server_playback(self): if self.server_playback.exit: self.shutdown() self.server_playback = None def do_server_playback(self, flow): """ This method should be called by child classes in the handle_request handler. Returns True if playback has taken place, None if not. """ if self.server_playback: rflow = self.server_playback.next_flow(flow) if not rflow: return None # FIXME response = Response._from_state(flow.request, rflow.response._get_state()) response._set_replay() flow.response = response if self.refresh_server_playback: response.refresh() flow.request.reply(response) if self.server_playback.count() == 0: self.stop_server_playback() return True return None def tick(self, q): if self.client_playback: e = [ self.client_playback.done(), self.client_playback.exit, self.state.active_flow_count() == 0 ] if all(e): self.shutdown() self.client_playback.tick(self) return controller.Master.tick(self, q) def duplicate_flow(self, f): return self.load_flow(f.copy()) def load_flow(self, f): """ Loads a flow, and returns a new flow object. """ if f.request: f.request.reply = controller.DummyReply() fr = self.handle_request(f.request) if f.response: f.response.reply = controller.DummyReply() self.handle_response(f.response) if f.error: f.error.reply = controller.DummyReply() self.handle_error(f.error) return fr def load_flows(self, fr): """ Load flows from a FlowReader object. """ for i in fr.stream(): self.load_flow(i) def process_new_request(self, f): if self.stickycookie_state: self.stickycookie_state.handle_request(f) if self.stickyauth_state: self.stickyauth_state.handle_request(f) if self.anticache: f.request.anticache() if self.anticomp: f.request.anticomp() if self.server_playback: pb = self.do_server_playback(f) if not pb: if self.kill_nonreplay: f.kill(self) else: f.request.reply() def process_new_response(self, f): if self.stickycookie_state: self.stickycookie_state.handle_response(f) def replay_request(self, f, block=False): """ Returns None if successful, or error message if not. """ if f.intercepting: return "Can't replay while intercepting..." if f.request.content == CONTENT_MISSING: return "Can't replay request with missing content..." if f.request: f.request._set_replay() if f.request.content: f.request.headers["Content-Length"] = [str(len(f.request.content))] f.response = None f.error = None self.process_new_request(f) rt = proxy.RequestReplayThread( self.server.config, f, self.masterq, ) rt.start() # pragma: no cover if block: rt.join() def handle_clientconnect(self, cc): self.run_script_hook("clientconnect", cc) cc.reply() def handle_clientdisconnect(self, r): self.run_script_hook("clientdisconnect", r) r.reply() def handle_serverconnection(self, sc): # To unify the mitmproxy script API, we call the script hook # "serverconnect" rather than "serverconnection". As things are handled # differently in libmproxy (ClientConnect + ClientDisconnect vs # ServerConnection class), there is no "serverdisonnect" event at the # moment. self.run_script_hook("serverconnect", sc) sc.reply() def handle_error(self, r): f = self.state.add_error(r) if f: self.run_script_hook("error", f) if self.client_playback: self.client_playback.clear(f) r.reply() return f def handle_request(self, r): if False and r.is_live(): # FIXME app = self.apps.get(r) if app: # FIXME: for the tcp proxy, use flow.client_conn.wfile err = app.serve(r, r.wfile, **{"mitmproxy.master": self}) if err: self.add_event("Error in wsgi app. %s"%err, "error") r.reply(proxy.KILL) return f = self.state.add_request(r) self.replacehooks.run(f) self.setheaders.run(f) self.run_script_hook("request", f) self.process_new_request(f) return f def handle_response(self, r): f = self.state.add_response(r) if f: self.replacehooks.run(f) self.setheaders.run(f) self.run_script_hook("response", f) if self.client_playback: self.client_playback.clear(f) self.process_new_response(f) if self.stream: self.stream.add(f) else: r.reply() return f def shutdown(self): self.unload_scripts() controller.Master.shutdown(self) if self.stream: for i in self.state._flow_list: if not i.response: self.stream.add(i) self.stop_stream() def start_stream(self, fp, filt): self.stream = FilteredFlowWriter(fp, filt) def stop_stream(self): self.stream.fo.close() self.stream = None class FlowWriter: def __init__(self, fo): self.fo = fo def add(self, flow): d = flow._get_state() tnetstring.dump(d, self.fo) class FlowReadError(Exception): @property def strerror(self): return self.args[0] class FlowReader: def __init__(self, fo): self.fo = fo def stream(self): """ Yields Flow objects from the dump. """ off = 0 try: while 1: data = tnetstring.load(self.fo) if tuple(data["version"][:2]) != version.IVERSION[:2]: v = ".".join(str(i) for i in data["version"]) raise FlowReadError("Incompatible serialized data version: %s"%v) off = self.fo.tell() yield protocol.protocols[data["conntype"]]["flow"]._from_state(data) except ValueError, v: # Error is due to EOF if self.fo.tell() == off and self.fo.read() == '': return raise FlowReadError("Invalid data format.") class FilteredFlowWriter: def __init__(self, fo, filt): self.fo = fo self.filt = filt def add(self, f): if self.filt and not f.match(self.filt): return d = f._get_state() tnetstring.dump(d, self.fo)