class RdpcapSource(Source): """Read packets from a PCAP file send them to low exit. .. code:: +----------+ >>-| |->> | | >-| [pcap]--|-> +----------+ """ def __init__(self, fname, name=None): Source.__init__(self, name=name) self.fname = fname self.f = PcapReader(self.fname) def start(self): self.f = PcapReader(self.fname) self.is_exhausted = False def stop(self): self.f.close() def fileno(self): return self.f.fileno() def check_recv(self): return True def deliver(self): try: p = self.f.recv() self._send(p) except EOFError: self.is_exhausted = True
class L2ListenTcpdump(SuperSocket): desc = "read packets at layer 2 using tcpdump" def __init__(self, iface=None, promisc=None, filter=None, nofilter=False, prog=None, *arg, **karg): self.outs = None args = ['-w', '-', '-s', '65535'] if iface is not None: args.extend(['-i', iface]) if not promisc: args.append('-p') if not nofilter: if conf.except_filter: if filter: filter = "(%s) and not (%s)" % (filter, conf.except_filter) else: filter = "not (%s)" % conf.except_filter if filter is not None: args.append(filter) self.ins = PcapReader(tcpdump(None, prog=prog, args=args, getfd=True)) def recv(self, x=MTU): return self.ins.recv(x)
class USBpcapSocket(SuperSocket): """ Read packets at layer 2 using USBPcapCMD """ nonblocking_socket = True @staticmethod def select(sockets, remain=None): return sockets def __init__(self, iface=None, *args, **karg): _usbpcap_check() if iface is None: warning("Available interfaces: [%s]", " ".join(x[0] for x in get_usbpcap_interfaces())) raise NameError("No interface specified !" " See get_usbpcap_interfaces()") iface = network_name(iface) self.outs = None args = ['-d', iface, '-b', '134217728', '-A', '-o', '-'] self.usbpcap_proc = subprocess.Popen([conf.prog.usbpcapcmd] + args, stdout=subprocess.PIPE, stderr=subprocess.PIPE) self.ins = PcapReader(self.usbpcap_proc.stdout) def recv(self, x=MTU): return self.ins.recv(x) def close(self): SuperSocket.close(self) self.usbpcap_proc.kill()
class USBpcapSocket(SuperSocket): """ Read packets at layer 2 using USBPcapCMD """ def __init__(self, iface=None, *args, **karg): _usbpcap_check() if iface is None: warning("Available interfaces: [%s]" % " ".join(x[0] for x in get_usbpcap_interfaces())) raise NameError("No interface specified !" " See get_usbpcap_interfaces()") self.outs = None args = ['-d', iface, '-b', '134217728', '-A', '-o', '-'] self.usbpcap_proc = subprocess.Popen( [conf.prog.usbpcapcmd] + args, stdout=subprocess.PIPE, stderr=subprocess.PIPE ) self.ins = PcapReader(self.usbpcap_proc.stdout) def recv(self, x=MTU): return self.ins.recv(x) def close(self): SuperSocket.close(self) self.usbpcap_proc.kill()
class L2ListenTcpdump(SuperSocket): desc = "read packets at layer 2 using tcpdump" def __init__(self, iface=None, promisc=None, filter=None, nofilter=False, prog=None, *arg, **karg): self.outs = None args = ['-w', '-', '-s', '65535'] if iface is not None: if WINDOWS: try: args.extend(['-i', iface.pcap_name]) except AttributeError: args.extend(['-i', iface]) else: args.extend(['-i', iface]) elif WINDOWS or DARWIN: args.extend(['-i', conf.iface.pcap_name if WINDOWS else conf.iface]) if not promisc: args.append('-p') if not nofilter: if conf.except_filter: if filter: filter = "(%s) and not (%s)" % (filter, conf.except_filter) else: filter = "not (%s)" % conf.except_filter if filter is not None: args.append(filter) self.tcpdump_proc = tcpdump(None, prog=prog, args=args, getproc=True) self.ins = PcapReader(self.tcpdump_proc.stdout) def recv(self, x=MTU): return self.ins.recv(x) def close(self): SuperSocket.close(self) self.tcpdump_proc.kill()
class RdpcapSource(Source): """Read packets from a PCAP file send them to low exit. +----------+ >>-| |->> | | >-| [pcap]--|-> +----------+ """ def __init__(self, fname, name=None): Source.__init__(self, name=name) self.fname = fname self.f = PcapReader(self.fname) def start(self): print("start") self.f = PcapReader(self.fname) self.is_exhausted = False def stop(self): print("stop") self.f.close() def fileno(self): return self.f.fileno() def check_recv(self): return True def deliver(self): p = self.f.recv() print("deliver %r" % p) if p is None: self.is_exhausted = True else: self._send(p)
def sniff(count=0, store=1, offline=None, prn = None, lfilter=None, L2socket=None, timeout=None, *arg, **karg): """Sniff packets sniff([count=0,] [prn=None,] [store=1,] [offline=None,] [lfilter=None,] + L2ListenSocket args) -> list of packets Select interface to sniff by setting conf.iface. Use show_interfaces() to see interface names. count: number of packets to capture. 0 means infinity store: wether to store sniffed packets or discard them prn: function to apply to each packet. If something is returned, it is displayed. Ex: ex: prn = lambda x: x.summary() filter: provide a BPF filter lfilter: python function applied to each packet to determine if further action may be done ex: lfilter = lambda x: x.haslayer(Padding) offline: pcap file to read packets from, instead of sniffing them timeout: stop sniffing after a given time (default: None) L2socket: use the provided L2socket """ c = 0 if offline is None: log_runtime.info('Sniffing on %s' % conf.iface) if L2socket is None: L2socket = conf.L2listen s = L2socket(type=ETH_P_ALL, *arg, **karg) else: flt = karg.get('filter') s = PcapReader(offline if flt is None else tcpdump(offline, args=["-w", "-", flt], getfd=True)) lst = [] if timeout is not None: stoptime = time.time()+timeout remain = None while 1: try: if timeout is not None: remain = stoptime-time.time() if remain <= 0: break try: p = s.recv(MTU) except PcapTimeoutElapsed: continue if p is None: break if lfilter and not lfilter(p): continue if store: lst.append(p) c += 1 if prn: r = prn(p) if r is not None: print r if 0 < count <= c: break except KeyboardInterrupt: break s.close() return plist.PacketList(lst,"Sniffed")
class RdpcapSource(Source): """Read packets from a PCAP file send them to low exit. +----------+ >>-| |->> | | >-| [pcap]--|-> +----------+ """ def __init__(self, fname, name=None): Source.__init__(self, name=name) self.fname = fname self.f = PcapReader(self.fname) def start(self): print "start" self.f = PcapReader(self.fname) self.is_exhausted = False def stop(self): print "stop" self.f.close() def fileno(self): return self.f.fileno() def deliver(self): p = self.f.recv() print "deliver %r" % p if p is None: self.is_exhausted = True else: self._send(p)
def sniff(count=0, store=1, offline=None, prn = None, lfilter=None, L2socket=None, timeout=None, *arg, **karg): """Sniff packets sniff([count=0,] [prn=None,] [store=1,] [offline=None,] [lfilter=None,] + L2ListenSocket args) -> list of packets Select interface to sniff by setting conf.iface. Use show_interfaces() to see interface names. count: number of packets to capture. 0 means infinity store: wether to store sniffed packets or discard them prn: function to apply to each packet. If something is returned, it is displayed. Ex: ex: prn = lambda x: x.summary() lfilter: python function applied to each packet to determine if further action may be done ex: lfilter = lambda x: x.haslayer(Padding) offline: pcap file to read packets from, instead of sniffing them timeout: stop sniffing after a given time (default: None) L2socket: use the provided L2socket """ c = 0 if offline is None: log_runtime.info('Sniffing on %s' % conf.iface) if L2socket is None: L2socket = conf.L2listen s = L2socket(type=ETH_P_ALL, *arg, **karg) else: s = PcapReader(offline) lst = [] if timeout is not None: stoptime = time.time()+timeout remain = None while 1: try: if timeout is not None: remain = stoptime-time.time() if remain <= 0: break try: p = s.recv(MTU) except PcapTimeoutElapsed: continue if p is None: break if lfilter and not lfilter(p): continue if store: lst.append(p) c += 1 if prn: r = prn(p) if r is not None: print(r) if count > 0 and c >= count: break except KeyboardInterrupt: break s.close() return plist.PacketList(lst,"Sniffed")
class L2ListenTcpdump(SuperSocket): desc = "read packets at layer 2 using tcpdump" def __init__( self, iface=None, # type: Optional[_GlobInterfaceType] promisc=False, # type: bool filter=None, # type: Optional[str] nofilter=False, # type: bool prog=None, # type: Optional[str] *arg, # type: Any **karg # type: Any ): # type: (...) -> None self.outs = None args = ['-w', '-', '-s', '65535'] if iface is None and (WINDOWS or DARWIN): iface = conf.iface self.iface = iface if iface is not None: args.extend(['-i', network_name(iface)]) if not promisc: args.append('-p') if not nofilter: if conf.except_filter: if filter: filter = "(%s) and not (%s)" % (filter, conf.except_filter) else: filter = "not (%s)" % conf.except_filter if filter is not None: args.append(filter) self.tcpdump_proc = tcpdump(None, prog=prog, args=args, getproc=True) self.reader = PcapReader(self.tcpdump_proc.stdout) self.ins = self.reader # type: ignore def recv(self, x=MTU): # type: (int) -> Optional[Packet] return self.reader.recv(x) def close(self): # type: () -> None SuperSocket.close(self) self.tcpdump_proc.kill() @staticmethod def select(sockets, remain=None): # type: (List[SuperSocket], Optional[float]) -> List[SuperSocket] if (WINDOWS or DARWIN): return sockets return SuperSocket.select(sockets, remain=remain)
class L2ListenTcpdump(SuperSocket): desc = "read packets at layer 2 using tcpdump" def __init__(self, iface=None, promisc=None, filter=None, nofilter=False, prog=None, *arg, **karg): self.outs = None args = ['-w', '-', '-s', '65535'] if iface is None and (WINDOWS or DARWIN): iface = conf.iface if WINDOWS: try: iface = iface.pcap_name except AttributeError: pass self.iface = iface if iface is not None: args.extend(['-i', self.iface]) if not promisc: args.append('-p') if not nofilter: if conf.except_filter: if filter: filter = "(%s) and not (%s)" % (filter, conf.except_filter) else: filter = "not (%s)" % conf.except_filter if filter is not None: args.append(filter) self.tcpdump_proc = tcpdump(None, prog=prog, args=args, getproc=True) self.ins = PcapReader(self.tcpdump_proc.stdout) def recv(self, x=MTU): return self.ins.recv(x) def close(self): SuperSocket.close(self) self.tcpdump_proc.kill() @staticmethod def select(sockets, remain=None): if (WINDOWS or DARWIN): return sockets, None return SuperSocket.select(sockets, remain=remain)
def mysniff(self, *arg, **karg): c = 0 if self.opened_socket is not None: s = self.opened_socket else: if self.offline is None: if self.L2socket is None: self.L2socket = conf.L2listen s = self.L2socket(type=ETH_P_ALL, *arg, **karg) else: s = PcapReader(self.offline) lst = [] if self.timeout is not None: stoptime = time.time() + self.timeout remain = None while 1: if not self.running: break try: if self.timeout is not None: remain = stoptime - time.time() if remain <= 0: break sel = select([s], [], [], remain) if s in sel[0]: p = s.recv(MTU) if p is None: break if self.lfilter and not self.lfilter(p): continue if self.store: lst.append(p) c += 1 if self.prn: r = self.prn(p) if r is not None: print r if self.stop_filter and self.stop_filter(p): break if 0 < self.count <= c: break except KeyboardInterrupt: break if self.opened_socket is None: s.close() return plist.PacketList(lst, "Sniffed")
def sniff(count=0, store=1, offline=None, prn=None, lfilter=None, L2socket=None, timeout=None, stopperTimeout=None, flag_dict=None, pkt_lst=pkt_lst, *arg, **karg): """Sniff packets sniff([count=0,] [prn=None,] [store=1,] [offline=None,] [lfilter=None,] + L2ListenSocket args) -> list of packets Select interface to sniff by setting conf.iface. Use show_interfaces() to see interface names. count: number of packets to capture. 0 means infinity store: wether to store sniffed packets or discard them prn: function to apply to each packet. If something is returned, it is displayed. Ex: ex: prn = lambda x: x.summary() lfilter: python function applied to each packet to determine if further action may be done ex: lfilter = lambda x: x.haslayer(Padding) offline: pcap file to read packets from, instead of sniffing them timeout: stop sniffing after a given time (default: None) L2socket: use the provided L2socket stop_callback: Call every loop to determine if we need to stop the capture """ mac = flag_dict['mac'] up = 0 down = 0 c = 0 last_time = '' if offline is None: if L2socket is None: L2socket = conf.L2listen s = L2socket(type=ETH_P_ALL, *arg, **karg) else: s = PcapReader(offline) global lst global length if timeout is not None: stoptime = time.time() + timeout remain = None if stopperTimeout is not None: stopperStoptime = time.time() + stopperTimeout remainStopper = None if (flag_dict['max']): s.recv_pkt_lst_init() while 1: try: if timeout is not None: remain = stoptime - time.time() if remain <= 0: break if stopperTimeout is not None: remainStopper = stopperStoptime - time.time() if remainStopper <= 0: if flag_dict['start'] == False: break stopperStoptime = time.time() + stopperTimeout remainStopper = stopperStoptime - time.time() ll = s.ins.datalink() if ll in conf.l2types: cls = conf.l2types[ll] else: cls = conf.default_l2 warning( "Unable to guess datalink type (interface=%s linktype=%i). Using %s" % (self.iface, ll, cls.name)) while (s.num_process >= s.num_capture): if (flag_dict['start'] == False): return (None) pass pkt, t = s.pkt_lst[s.num_process][0], s.pkt_lst[ s.num_process][1] ts, pkt = pkt # if scapy.arch.WINDOWS and pkt is None: #raise PcapTimeoutElapsed try: pkt = cls(pkt) except KeyboardInterrupt: raise except: if conf.debug_dissector: raise pkt = conf.raw_layer(pkt) s.num_process += 1 p = pkt length = s.num_process if p is None: break if lfilter and not lfilter(p): continue if store: lst.append(p) pkt_lst.put([bytes(p), t]) c += 1 if prn: r = prn(p) if r is not None: print(r) if count > 0 and c >= count: break except KeyboardInterrupt: break s.close() return plist.PacketList(lst, "Sniffed") else: while 1: try: if timeout is not None: remain = stoptime - time.time() if remain <= 0: break if stopperTimeout is not None: remainStopper = stopperStoptime - time.time() if remainStopper <= 0: if flag_dict['start'] == False: break stopperStoptime = time.time() + stopperTimeout remainStopper = stopperStoptime - time.time() try: p = s.recv(MTU) except PcapTimeoutElapsed: continue if p is None: break if lfilter and not lfilter(p): continue if store: lst.append(p) pkt_lst.put([bytes(p), datetime.now().strftime("%H:%M:%S")]) #print (length,str(datetime.now()),bytes(p)) c += 1 if prn: r = prn(p) if r is not None: print(r) if count > 0 and c >= count: break except KeyboardInterrupt: break s.close() return plist.PacketList(lst, "Sniffed")
class VppPGInterface(VppInterface): """ VPP packet-generator interface """ @property def pg_index(self): """packet-generator interface index assigned by VPP""" return self._pg_index @property def gso_enabled(self): """gso enabled on packet-generator interface""" if self._gso_enabled == 0: return "gso-disabled" return "gso-enabled" @property def gso_size(self): """gso size on packet-generator interface""" return self._gso_size @property def out_path(self): """pcap file path - captured packets""" return self._out_path @property def in_path(self): """ pcap file path - injected packets""" return self._in_path @property def capture_cli(self): """CLI string to start capture on this interface""" return self._capture_cli @property def cap_name(self): """capture name for this interface""" return self._cap_name @property def input_cli(self): """CLI string to load the injected packets""" if self._nb_replays is not None: return "%s limit %d" % (self._input_cli, self._nb_replays) if self._worker is not None: return "%s worker %d" % (self._input_cli, self._worker) return self._input_cli @property def in_history_counter(self): """Self-incrementing counter used when renaming old pcap files""" v = self._in_history_counter self._in_history_counter += 1 return v @property def out_history_counter(self): """Self-incrementing counter used when renaming old pcap files""" v = self._out_history_counter self._out_history_counter += 1 return v def __init__(self, test, pg_index, gso, gso_size): """ Create VPP packet-generator interface """ super(VppPGInterface, self).__init__(test) r = test.vapi.pg_create_interface(pg_index, gso, gso_size) self.set_sw_if_index(r.sw_if_index) self._in_history_counter = 0 self._out_history_counter = 0 self._out_assert_counter = 0 self._pg_index = pg_index self._gso_enabled = gso self._gso_size = gso_size self._out_file = "pg%u_out.pcap" % self.pg_index self._out_path = self.test.tempdir + "/" + self._out_file self._in_file = "pg%u_in.pcap" % self.pg_index self._in_path = self.test.tempdir + "/" + self._in_file self._capture_cli = "packet-generator capture pg%u pcap %s" % ( self.pg_index, self.out_path) self._cap_name = "pcap%u-sw_if_index-%s" % (self.pg_index, self.sw_if_index) self._input_cli = \ "packet-generator new pcap %s source pg%u name %s" % ( self.in_path, self.pg_index, self.cap_name) self._nb_replays = None def _rename_previous_capture_file(self, path, counter, file): # if a file from a previous capture exists, rename it. try: if os.path.isfile(path): name = "%s/history.[timestamp:%f].[%s-counter:%04d].%s" % \ (self.test.tempdir, time.time(), self.name, counter, file) self.test.logger.debug("Renaming %s->%s" % (path, name)) os.rename(path, name) except OSError: self.test.logger.debug("OSError: Could not rename %s %s" % (path, file)) def enable_capture(self): """ Enable capture on this packet-generator interface of at most n packets. If n < 0, this is no limit """ # disable the capture to flush the capture self.disable_capture() self._rename_previous_capture_file(self.out_path, self.out_history_counter, self._out_file) # FIXME this should be an API, but no such exists atm self.test.vapi.cli(self.capture_cli) self._pcap_reader = None def disable_capture(self): self.test.vapi.cli("%s disable" % self.capture_cli) def add_stream(self, pkts, nb_replays=None, worker=None): """ Add a stream of packets to this packet-generator :param pkts: iterable packets """ self._worker = worker self._nb_replays = nb_replays self._rename_previous_capture_file(self.in_path, self.in_history_counter, self._in_file) wrpcap(self.in_path, pkts) self.test.register_capture(self.cap_name) # FIXME this should be an API, but no such exists atm self.test.vapi.cli(self.input_cli) def generate_debug_aid(self, kind): """ Create a hardlink to the out file with a counter and a file containing stack trace to ease debugging in case of multiple capture files present. """ self.test.logger.debug("Generating debug aid for %s on %s" % (kind, self._name)) link_path, stack_path = [ "%s/debug_%s_%s_%s.%s" % (self.test.tempdir, self._name, self._out_assert_counter, kind, suffix) for suffix in ["pcap", "stack"] ] os.link(self.out_path, link_path) with open(stack_path, "w") as f: f.writelines(format_stack()) self._out_assert_counter += 1 def _get_capture(self, timeout, filter_out_fn=is_ipv6_misc): """ Helper method to get capture and filter it """ try: if not self.wait_for_capture_file(timeout): return None output = rdpcap(self.out_path) self.test.logger.debug("Capture has %s packets" % len(output.res)) except: self.test.logger.debug("Exception in scapy.rdpcap (%s): %s" % (self.out_path, format_exc())) return None before = len(output.res) if filter_out_fn: output.res = [p for p in output.res if not filter_out_fn(p)] removed = before - len(output.res) if removed: self.test.logger.debug( "Filtered out %s packets from capture (returning %s)" % (removed, len(output.res))) return output def get_capture(self, expected_count=None, remark=None, timeout=1, filter_out_fn=is_ipv6_misc): """ Get captured packets :param expected_count: expected number of packets to capture, if None, then self.test.packet_count_for_dst_pg_idx is used to lookup the expected count :param remark: remark printed into debug logs :param timeout: how long to wait for packets :param filter_out_fn: filter applied to each packet, packets for which the filter returns True are removed from capture :returns: iterable packets """ remaining_time = timeout capture = None name = self.name if remark is None else "%s (%s)" % (self.name, remark) based_on = "based on provided argument" if expected_count is None: expected_count = \ self.test.get_packet_count_for_if_idx(self.sw_if_index) based_on = "based on stored packet_infos" if expected_count == 0: raise Exception( "Internal error, expected packet count for %s is 0!" % name) self.test.logger.debug("Expecting to capture %s (%s) packets on %s" % (expected_count, based_on, name)) while remaining_time > 0: before = time.time() capture = self._get_capture(remaining_time, filter_out_fn) elapsed_time = time.time() - before if capture: if len(capture.res) == expected_count: # bingo, got the packets we expected return capture elif len(capture.res) > expected_count: self.test.logger.error( ppc("Unexpected packets captured:", capture)) break else: self.test.logger.debug("Partial capture containing %s " "packets doesn't match expected " "count %s (yet?)" % (len(capture.res), expected_count)) elif expected_count == 0: # bingo, got None as we expected - return empty capture return PacketList() remaining_time -= elapsed_time if capture: self.generate_debug_aid("count-mismatch") raise Exception("Captured packets mismatch, captured %s packets, " "expected %s packets on %s" % (len(capture.res), expected_count, name)) else: raise Exception("No packets captured on %s" % name) def assert_nothing_captured(self, remark=None, filter_out_fn=is_ipv6_misc): """ Assert that nothing unfiltered was captured on interface :param remark: remark printed into debug logs :param filter_out_fn: filter applied to each packet, packets for which the filter returns True are removed from capture """ if os.path.isfile(self.out_path): try: capture = self.get_capture(0, remark=remark, filter_out_fn=filter_out_fn) if not capture or len(capture.res) == 0: # junk filtered out, we're good return except: pass self.generate_debug_aid("empty-assert") if remark: raise AssertionError( "Non-empty capture file present for interface %s (%s)" % (self.name, remark)) else: raise AssertionError("Capture file present for interface %s" % self.name) def wait_for_pg_stop(self): # wait till packet-generator is stopped # "show packet-generator" while it is still running gives this: # Name Enabled Count Parameters # pcap0-sw_if_inde Yes 64 limit 64, ... # # also have a 5-minute timeout just in case things go terribly wrong... deadline = time.time() + 300 while self.test.vapi.cli('show packet-generator').find("Yes") != -1: self._test.sleep(0.01) # yield if time.time() > deadline: self.test.logger.debug("Timeout waiting for pg to stop") break def wait_for_capture_file(self, timeout=1): """ Wait until pcap capture file appears :param timeout: How long to wait for the packet (default 1s) :returns: True/False if the file is present or appears within timeout """ self.wait_for_pg_stop() deadline = time.time() + timeout if not os.path.isfile(self.out_path): self.test.logger.debug("Waiting for capture file %s to appear, " "timeout is %ss" % (self.out_path, timeout)) else: self.test.logger.debug("Capture file %s already exists" % self.out_path) return True while time.time() < deadline: if os.path.isfile(self.out_path): break self._test.sleep(0) # yield if os.path.isfile(self.out_path): self.test.logger.debug("Capture file appeared after %fs" % (time.time() - (deadline - timeout))) else: self.test.logger.debug("Timeout - capture file still nowhere") return False return True def verify_enough_packet_data_in_pcap(self): """ Check if enough data is available in file handled by internal pcap reader so that a whole packet can be read. :returns: True if enough data present, else False """ orig_pos = self._pcap_reader.f.tell() # save file position enough_data = False # read packet header from pcap packet_header_size = 16 caplen = None end_pos = None hdr = self._pcap_reader.f.read(packet_header_size) if len(hdr) == packet_header_size: # parse the capture length - caplen sec, usec, caplen, wirelen = struct.unpack( self._pcap_reader.endian + "IIII", hdr) self._pcap_reader.f.seek(0, 2) # seek to end of file end_pos = self._pcap_reader.f.tell() # get position at end if end_pos >= orig_pos + len(hdr) + caplen: enough_data = True # yay, we have enough data self._pcap_reader.f.seek(orig_pos, 0) # restore original position return enough_data def wait_for_packet(self, timeout, filter_out_fn=is_ipv6_misc): """ Wait for next packet captured with a timeout :param timeout: How long to wait for the packet :returns: Captured packet if no packet arrived within timeout :raises Exception: if no packet arrives within timeout """ deadline = time.time() + timeout if self._pcap_reader is None: if not self.wait_for_capture_file(timeout): raise CaptureTimeoutError("Capture file %s did not appear " "within timeout" % self.out_path) while time.time() < deadline: try: self._pcap_reader = PcapReader(self.out_path) break except: self.test.logger.debug( "Exception in scapy.PcapReader(%s): %s" % (self.out_path, format_exc())) if not self._pcap_reader: raise CaptureTimeoutError("Capture file %s did not appear within " "timeout" % self.out_path) poll = False if timeout > 0: self.test.logger.debug("Waiting for packet") else: poll = True self.test.logger.debug("Polling for packet") while time.time() < deadline or poll: if not self.verify_enough_packet_data_in_pcap(): self._test.sleep(0) # yield poll = False continue p = self._pcap_reader.recv() if p is not None: if filter_out_fn is not None and filter_out_fn(p): self.test.logger.debug( "Packet received after %ss was filtered out" % (time.time() - (deadline - timeout))) else: self.test.logger.debug("Packet received after %fs" % (time.time() - (deadline - timeout))) return p self._test.sleep(0) # yield poll = False self.test.logger.debug("Timeout - no packets received") raise CaptureTimeoutError("Packet didn't arrive within timeout") def create_arp_req(self): """Create ARP request applicable for this interface""" return (Ether(dst="ff:ff:ff:ff:ff:ff", src=self.remote_mac) / ARP(op=ARP.who_has, pdst=self.local_ip4, psrc=self.remote_ip4, hwsrc=self.remote_mac)) def create_ndp_req(self): """Create NDP - NS applicable for this interface""" nsma = in6_getnsma(inet_pton(socket.AF_INET6, self.local_ip6)) d = inet_ntop(socket.AF_INET6, nsma) return (Ether(dst=in6_getnsmac(nsma)) / IPv6(dst=d, src=self.remote_ip6) / ICMPv6ND_NS(tgt=self.local_ip6) / ICMPv6NDOptSrcLLAddr(lladdr=self.remote_mac)) def resolve_arp(self, pg_interface=None): """Resolve ARP using provided packet-generator interface :param pg_interface: interface used to resolve, if None then this interface is used """ if pg_interface is None: pg_interface = self self.test.logger.info("Sending ARP request for %s on port %s" % (self.local_ip4, pg_interface.name)) arp_req = self.create_arp_req() pg_interface.add_stream(arp_req) pg_interface.enable_capture() self.test.pg_start() self.test.logger.info(self.test.vapi.cli("show trace")) try: captured_packet = pg_interface.wait_for_packet(1) except: self.test.logger.info("No ARP received on port %s" % pg_interface.name) return arp_reply = captured_packet.copy() # keep original for exception try: if arp_reply[ARP].op == ARP.is_at: self.test.logger.info("VPP %s MAC address is %s " % (self.name, arp_reply[ARP].hwsrc)) self._local_mac = arp_reply[ARP].hwsrc else: self.test.logger.info("No ARP received on port %s" % pg_interface.name) except: self.test.logger.error( ppp("Unexpected response to ARP request:", captured_packet)) raise def resolve_ndp(self, pg_interface=None, timeout=1): """Resolve NDP using provided packet-generator interface :param pg_interface: interface used to resolve, if None then this interface is used :param timeout: how long to wait for response before giving up """ if pg_interface is None: pg_interface = self self.test.logger.info("Sending NDP request for %s on port %s" % (self.local_ip6, pg_interface.name)) ndp_req = self.create_ndp_req() pg_interface.add_stream(ndp_req) pg_interface.enable_capture() self.test.pg_start() now = time.time() deadline = now + timeout # Enabling IPv6 on an interface can generate more than the # ND reply we are looking for (namely MLD). So loop through # the replies to look for want we want. while now < deadline: try: captured_packet = pg_interface.wait_for_packet( deadline - now, filter_out_fn=None) except: self.test.logger.error( "Timeout while waiting for NDP response") raise ndp_reply = captured_packet.copy() # keep original for exception try: ndp_na = ndp_reply[ICMPv6ND_NA] opt = ndp_na[ICMPv6NDOptDstLLAddr] self.test.logger.info("VPP %s MAC address is %s " % (self.name, opt.lladdr)) self._local_mac = opt.lladdr self.test.logger.debug(self.test.vapi.cli("show trace")) # we now have the MAC we've been after return except: self.test.logger.info( ppp("Unexpected response to NDP request:", captured_packet)) now = time.time() self.test.logger.debug(self.test.vapi.cli("show trace")) raise Exception("Timeout while waiting for NDP response")
class VppPGInterface(VppInterface): """ VPP packet-generator interface """ @property def pg_index(self): """packet-generator interface index assigned by VPP""" return self._pg_index @property def out_path(self): """pcap file path - captured packets""" return self._out_path @property def in_path(self): """ pcap file path - injected packets""" return self._in_path @property def capture_cli(self): """CLI string to start capture on this interface""" return self._capture_cli @property def cap_name(self): """capture name for this interface""" return self._cap_name @property def input_cli(self): """CLI string to load the injected packets""" return self._input_cli @property def in_history_counter(self): """Self-incrementing counter used when renaming old pcap files""" v = self._in_history_counter self._in_history_counter += 1 return v @property def out_history_counter(self): """Self-incrementing counter used when renaming old pcap files""" v = self._out_history_counter self._out_history_counter += 1 return v def __init__(self, test, pg_index): """ Create VPP packet-generator interface """ super(VppPGInterface, self).__init__(test) r = test.vapi.pg_create_interface(pg_index) self.set_sw_if_index(r.sw_if_index) self._in_history_counter = 0 self._out_history_counter = 0 self._out_assert_counter = 0 self._pg_index = pg_index self._out_file = "pg%u_out.pcap" % self.pg_index self._out_path = self.test.tempdir + "/" + self._out_file self._in_file = "pg%u_in.pcap" % self.pg_index self._in_path = self.test.tempdir + "/" + self._in_file self._capture_cli = "packet-generator capture pg%u pcap %s" % ( self.pg_index, self.out_path) self._cap_name = "pcap%u" % self.sw_if_index self._input_cli = \ "packet-generator new pcap %s source pg%u name %s" % ( self.in_path, self.pg_index, self.cap_name) def enable_capture(self): """ Enable capture on this packet-generator interface""" try: if os.path.isfile(self.out_path): name = "%s/history.[timestamp:%f].[%s-counter:%04d].%s" % \ (self.test.tempdir, time.time(), self.name, self.out_history_counter, self._out_file) self.test.logger.debug("Renaming %s->%s" % (self.out_path, name)) os.rename(self.out_path, name) except: pass # FIXME this should be an API, but no such exists atm self.test.vapi.cli(self.capture_cli) self._pcap_reader = None def add_stream(self, pkts): """ Add a stream of packets to this packet-generator :param pkts: iterable packets """ try: if os.path.isfile(self.in_path): name = "%s/history.[timestamp:%f].[%s-counter:%04d].%s" %\ (self.test.tempdir, time.time(), self.name, self.in_history_counter, self._in_file) self.test.logger.debug("Renaming %s->%s" % (self.in_path, name)) os.rename(self.in_path, name) except: pass wrpcap(self.in_path, pkts) self.test.register_capture(self.cap_name) # FIXME this should be an API, but no such exists atm self.test.vapi.cli(self.input_cli) def generate_debug_aid(self, kind): """ Create a hardlink to the out file with a counter and a file containing stack trace to ease debugging in case of multiple capture files present. """ self.test.logger.debug("Generating debug aid for %s on %s" % (kind, self._name)) link_path, stack_path = ["%s/debug_%s_%s_%s.%s" % (self.test.tempdir, self._name, self._out_assert_counter, kind, suffix) for suffix in ["pcap", "stack"] ] os.link(self.out_path, link_path) with open(stack_path, "w") as f: f.writelines(format_stack()) self._out_assert_counter += 1 def _get_capture(self, timeout, filter_out_fn=is_ipv6_misc): """ Helper method to get capture and filter it """ try: if not self.wait_for_capture_file(timeout): return None output = rdpcap(self.out_path) self.test.logger.debug("Capture has %s packets" % len(output.res)) except: self.test.logger.debug("Exception in scapy.rdpcap (%s): %s" % (self.out_path, format_exc())) return None before = len(output.res) if filter_out_fn: output.res = [p for p in output.res if not filter_out_fn(p)] removed = before - len(output.res) if removed: self.test.logger.debug( "Filtered out %s packets from capture (returning %s)" % (removed, len(output.res))) return output def get_capture(self, expected_count=None, remark=None, timeout=1, filter_out_fn=is_ipv6_misc): """ Get captured packets :param expected_count: expected number of packets to capture, if None, then self.test.packet_count_for_dst_pg_idx is used to lookup the expected count :param remark: remark printed into debug logs :param timeout: how long to wait for packets :param filter_out_fn: filter applied to each packet, packets for which the filter returns True are removed from capture :returns: iterable packets """ remaining_time = timeout capture = None name = self.name if remark is None else "%s (%s)" % (self.name, remark) based_on = "based on provided argument" if expected_count is None: expected_count = \ self.test.get_packet_count_for_if_idx(self.sw_if_index) based_on = "based on stored packet_infos" if expected_count == 0: raise Exception( "Internal error, expected packet count for %s is 0!" % name) self.test.logger.debug("Expecting to capture %s (%s) packets on %s" % ( expected_count, based_on, name)) while remaining_time > 0: before = time.time() capture = self._get_capture(remaining_time, filter_out_fn) elapsed_time = time.time() - before if capture: if len(capture.res) == expected_count: # bingo, got the packets we expected return capture elif len(capture.res) > expected_count: self.test.logger.error( ppc("Unexpected packets captured:", capture)) break else: self.test.logger.debug("Partial capture containing %s " "packets doesn't match expected " "count %s (yet?)" % (len(capture.res), expected_count)) elif expected_count == 0: # bingo, got None as we expected - return empty capture return PacketList() remaining_time -= elapsed_time if capture: self.generate_debug_aid("count-mismatch") raise Exception("Captured packets mismatch, captured %s packets, " "expected %s packets on %s" % (len(capture.res), expected_count, name)) else: raise Exception("No packets captured on %s" % name) def assert_nothing_captured(self, remark=None, filter_out_fn=is_ipv6_misc): """ Assert that nothing unfiltered was captured on interface :param remark: remark printed into debug logs :param filter_out_fn: filter applied to each packet, packets for which the filter returns True are removed from capture """ if os.path.isfile(self.out_path): try: capture = self.get_capture( 0, remark=remark, filter_out_fn=filter_out_fn) if not capture or len(capture.res) == 0: # junk filtered out, we're good return except: pass self.generate_debug_aid("empty-assert") if remark: raise AssertionError( "Non-empty capture file present for interface %s (%s)" % (self.name, remark)) else: raise AssertionError("Capture file present for interface %s" % self.name) def wait_for_capture_file(self, timeout=1): """ Wait until pcap capture file appears :param timeout: How long to wait for the packet (default 1s) :returns: True/False if the file is present or appears within timeout """ deadline = time.time() + timeout if not os.path.isfile(self.out_path): self.test.logger.debug("Waiting for capture file %s to appear, " "timeout is %ss" % (self.out_path, timeout)) else: self.test.logger.debug("Capture file %s already exists" % self.out_path) return True while time.time() < deadline: if os.path.isfile(self.out_path): break self._test.sleep(0) # yield if os.path.isfile(self.out_path): self.test.logger.debug("Capture file appeared after %fs" % (time.time() - (deadline - timeout))) else: self.test.logger.debug("Timeout - capture file still nowhere") return False return True def verify_enough_packet_data_in_pcap(self): """ Check if enough data is available in file handled by internal pcap reader so that a whole packet can be read. :returns: True if enough data present, else False """ orig_pos = self._pcap_reader.f.tell() # save file position enough_data = False # read packet header from pcap packet_header_size = 16 caplen = None end_pos = None hdr = self._pcap_reader.f.read(packet_header_size) if len(hdr) == packet_header_size: # parse the capture length - caplen sec, usec, caplen, wirelen = struct.unpack( self._pcap_reader.endian + "IIII", hdr) self._pcap_reader.f.seek(0, 2) # seek to end of file end_pos = self._pcap_reader.f.tell() # get position at end if end_pos >= orig_pos + len(hdr) + caplen: enough_data = True # yay, we have enough data self._pcap_reader.f.seek(orig_pos, 0) # restore original position return enough_data def wait_for_packet(self, timeout, filter_out_fn=is_ipv6_misc): """ Wait for next packet captured with a timeout :param timeout: How long to wait for the packet :returns: Captured packet if no packet arrived within timeout :raises Exception: if no packet arrives within timeout """ deadline = time.time() + timeout if self._pcap_reader is None: if not self.wait_for_capture_file(timeout): raise CaptureTimeoutError("Capture file %s did not appear " "within timeout" % self.out_path) while time.time() < deadline: try: self._pcap_reader = PcapReader(self.out_path) break except: self.test.logger.debug( "Exception in scapy.PcapReader(%s): %s" % (self.out_path, format_exc())) if not self._pcap_reader: raise CaptureTimeoutError("Capture file %s did not appear within " "timeout" % self.out_path) poll = False if timeout > 0: self.test.logger.debug("Waiting for packet") else: poll = True self.test.logger.debug("Polling for packet") while time.time() < deadline or poll: if not self.verify_enough_packet_data_in_pcap(): self._test.sleep(0) # yield poll = False continue p = self._pcap_reader.recv() if p is not None: if filter_out_fn is not None and filter_out_fn(p): self.test.logger.debug( "Packet received after %ss was filtered out" % (time.time() - (deadline - timeout))) else: self.test.logger.debug( "Packet received after %fs" % (time.time() - (deadline - timeout))) return p self._test.sleep(0) # yield poll = False self.test.logger.debug("Timeout - no packets received") raise CaptureTimeoutError("Packet didn't arrive within timeout") def create_arp_req(self): """Create ARP request applicable for this interface""" return (Ether(dst="ff:ff:ff:ff:ff:ff", src=self.remote_mac) / ARP(op=ARP.who_has, pdst=self.local_ip4, psrc=self.remote_ip4, hwsrc=self.remote_mac)) def create_ndp_req(self): """Create NDP - NS applicable for this interface""" nsma = in6_getnsma(inet_pton(socket.AF_INET6, self.local_ip6)) d = inet_ntop(socket.AF_INET6, nsma) return (Ether(dst=in6_getnsmac(nsma)) / IPv6(dst=d, src=self.remote_ip6) / ICMPv6ND_NS(tgt=self.local_ip6) / ICMPv6NDOptSrcLLAddr(lladdr=self.remote_mac)) def resolve_arp(self, pg_interface=None): """Resolve ARP using provided packet-generator interface :param pg_interface: interface used to resolve, if None then this interface is used """ if pg_interface is None: pg_interface = self self.test.logger.info("Sending ARP request for %s on port %s" % (self.local_ip4, pg_interface.name)) arp_req = self.create_arp_req() pg_interface.add_stream(arp_req) pg_interface.enable_capture() self.test.pg_start() self.test.logger.info(self.test.vapi.cli("show trace")) try: captured_packet = pg_interface.wait_for_packet(1) except: self.test.logger.info("No ARP received on port %s" % pg_interface.name) return arp_reply = captured_packet.copy() # keep original for exception # Make Dot1AD packet content recognizable to scapy if arp_reply.type == 0x88a8: arp_reply.type = 0x8100 arp_reply = Ether(scapy.compat.raw(arp_reply)) try: if arp_reply[ARP].op == ARP.is_at: self.test.logger.info("VPP %s MAC address is %s " % (self.name, arp_reply[ARP].hwsrc)) self._local_mac = arp_reply[ARP].hwsrc else: self.test.logger.info("No ARP received on port %s" % pg_interface.name) except: self.test.logger.error( ppp("Unexpected response to ARP request:", captured_packet)) raise def resolve_ndp(self, pg_interface=None, timeout=1): """Resolve NDP using provided packet-generator interface :param pg_interface: interface used to resolve, if None then this interface is used :param timeout: how long to wait for response before giving up """ if pg_interface is None: pg_interface = self self.test.logger.info("Sending NDP request for %s on port %s" % (self.local_ip6, pg_interface.name)) ndp_req = self.create_ndp_req() pg_interface.add_stream(ndp_req) pg_interface.enable_capture() self.test.pg_start() now = time.time() deadline = now + timeout # Enabling IPv6 on an interface can generate more than the # ND reply we are looking for (namely MLD). So loop through # the replies to look for want we want. while now < deadline: try: captured_packet = pg_interface.wait_for_packet( deadline - now, filter_out_fn=None) except: self.test.logger.error( "Timeout while waiting for NDP response") raise ndp_reply = captured_packet.copy() # keep original for exception # Make Dot1AD packet content recognizable to scapy if ndp_reply.type == 0x88a8: self._test.logger.info( "Replacing EtherType: 0x88a8 with " "0x8100 and regenerating Ethernet header. ") ndp_reply.type = 0x8100 ndp_reply = Ether(scapy.compat.raw(ndp_reply)) try: ndp_na = ndp_reply[ICMPv6ND_NA] opt = ndp_na[ICMPv6NDOptDstLLAddr] self.test.logger.info("VPP %s MAC address is %s " % (self.name, opt.lladdr)) self._local_mac = opt.lladdr self.test.logger.debug(self.test.vapi.cli("show trace")) # we now have the MAC we've been after return except: self.test.logger.info( ppp("Unexpected response to NDP request:", captured_packet)) now = time.time() self.test.logger.debug(self.test.vapi.cli("show trace")) raise Exception("Timeout while waiting for NDP response")
class VppPGInterface(VppInterface): """ VPP packet-generator interface """ @property def pg_index(self): """packet-generator interface index assigned by VPP""" return self._pg_index @property def out_path(self): """pcap file path - captured packets""" return self._out_path @property def in_path(self): """ pcap file path - injected packets""" return self._in_path @property def capture_cli(self): """CLI string to start capture on this interface""" return self._capture_cli @property def cap_name(self): """capture name for this interface""" return self._cap_name @property def input_cli(self): """CLI string to load the injected packets""" return self._input_cli @property def in_history_counter(self): """Self-incrementing counter used when renaming old pcap files""" v = self._in_history_counter self._in_history_counter += 1 return v @property def out_history_counter(self): """Self-incrementing counter used when renaming old pcap files""" v = self._out_history_counter self._out_history_counter += 1 return v def __init__(self, test, pg_index): """ Create VPP packet-generator interface """ r = test.vapi.pg_create_interface(pg_index) self._sw_if_index = r.sw_if_index super(VppPGInterface, self).__init__(test) self._in_history_counter = 0 self._out_history_counter = 0 self._pg_index = pg_index self._out_file = "pg%u_out.pcap" % self.pg_index self._out_path = self.test.tempdir + "/" + self._out_file self._in_file = "pg%u_in.pcap" % self.pg_index self._in_path = self.test.tempdir + "/" + self._in_file self._capture_cli = "packet-generator capture pg%u pcap %s" % ( self.pg_index, self.out_path) self._cap_name = "pcap%u" % self.sw_if_index self._input_cli = "packet-generator new pcap %s source pg%u name %s" % ( self.in_path, self.pg_index, self.cap_name) def enable_capture(self): """ Enable capture on this packet-generator interface""" try: if os.path.isfile(self.out_path): os.rename( self.out_path, "%s/history.[timestamp:%f].[%s-counter:%04d].%s" % (self.test.tempdir, time.time(), self.name, self.out_history_counter, self._out_file)) except: pass # FIXME this should be an API, but no such exists atm self.test.vapi.cli(self.capture_cli) self._pcap_reader = None def add_stream(self, pkts): """ Add a stream of packets to this packet-generator :param pkts: iterable packets """ try: if os.path.isfile(self.in_path): os.rename( self.in_path, "%s/history.[timestamp:%f].[%s-counter:%04d].%s" % (self.test.tempdir, time.time(), self.name, self.in_history_counter, self._in_file)) except: pass wrpcap(self.in_path, pkts) self.test.register_capture(self.cap_name) # FIXME this should be an API, but no such exists atm self.test.vapi.cli(self.input_cli) def get_capture(self, remark=None, filter_fn=is_ipv6_misc): """ Get captured packets :param remark: remark printed into debug logs :param filter_fn: filter applied to each packet, packets for which the filter returns True are removed from capture :returns: iterable packets """ try: self.wait_for_capture_file() output = rdpcap(self.out_path) self.test.logger.debug("Capture has %s packets" % len(output.res)) except IOError: # TODO self.test.logger.debug( "File %s does not exist, probably because no" " packets arrived" % self.out_path) if remark: raise Exception("No packets captured on %s(%s)" % (self.name, remark)) else: raise Exception("No packets captured on %s" % self.name) before = len(output.res) if filter_fn: output.res = [p for p in output.res if not filter_fn(p)] removed = len(output.res) - before if removed: self.test.logger.debug( "Filtered out %s packets from capture (returning %s)" % (removed, len(output.res))) return output def assert_nothing_captured(self, remark=None): if os.path.isfile(self.out_path): try: capture = self.get_capture(remark=remark) self.test.logger.error( ppc("Unexpected packets captured:", capture)) except: pass if remark: raise AssertionError( "Capture file present for interface %s(%s)" % (self.name, remark)) else: raise AssertionError("Capture file present for interface %s" % self.name) def wait_for_capture_file(self, timeout=1): """ Wait until pcap capture file appears :param timeout: How long to wait for the packet (default 1s) :raises Exception: if the capture file does not appear within timeout """ limit = time.time() + timeout if not os.path.isfile(self.out_path): self.test.logger.debug( "Waiting for capture file to appear, timeout is %ss", timeout) else: self.test.logger.debug("Capture file already exists") return while time.time() < limit: if os.path.isfile(self.out_path): break time.sleep(0) # yield if os.path.isfile(self.out_path): self.test.logger.debug("Capture file appeared after %fs" % (time.time() - (limit - timeout))) else: self.test.logger.debug("Timeout - capture file still nowhere") raise Exception("Capture file did not appear within timeout") def wait_for_packet(self, timeout): """ Wait for next packet captured with a timeout :param timeout: How long to wait for the packet :returns: Captured packet if no packet arrived within timeout :raises Exception: if no packet arrives within timeout """ limit = time.time() + timeout if self._pcap_reader is None: self.wait_for_capture_file(timeout) self._pcap_reader = PcapReader(self.out_path) self.test.logger.debug("Waiting for packet") while time.time() < limit: p = self._pcap_reader.recv() if p is not None: self.test.logger.debug("Packet received after %fs", (time.time() - (limit - timeout))) return p time.sleep(0) # yield self.test.logger.debug("Timeout - no packets received") raise Exception("Packet didn't arrive within timeout") def create_arp_req(self): """Create ARP request applicable for this interface""" return (Ether(dst="ff:ff:ff:ff:ff:ff", src=self.remote_mac) / ARP(op=ARP.who_has, pdst=self.local_ip4, psrc=self.remote_ip4, hwsrc=self.remote_mac)) def create_ndp_req(self): """Create NDP - NS applicable for this interface""" return (Ether(dst="ff:ff:ff:ff:ff:ff", src=self.remote_mac) / IPv6(src=self.remote_ip6, dst=self.local_ip6) / ICMPv6ND_NS(tgt=self.local_ip6) / ICMPv6NDOptSrcLLAddr(lladdr=self.remote_mac)) def resolve_arp(self, pg_interface=None): """Resolve ARP using provided packet-generator interface :param pg_interface: interface used to resolve, if None then this interface is used """ if pg_interface is None: pg_interface = self self.test.logger.info("Sending ARP request for %s on port %s" % (self.local_ip4, pg_interface.name)) arp_req = self.create_arp_req() pg_interface.add_stream(arp_req) pg_interface.enable_capture() self.test.pg_start() self.test.logger.info(self.test.vapi.cli("show trace")) try: arp_reply = pg_interface.get_capture(filter_fn=None) except: self.test.logger.info("No ARP received on port %s" % pg_interface.name) return arp_reply = arp_reply[0] # Make Dot1AD packet content recognizable to scapy if arp_reply.type == 0x88a8: arp_reply.type = 0x8100 arp_reply = Ether(str(arp_reply)) try: if arp_reply[ARP].op == ARP.is_at: self.test.logger.info("VPP %s MAC address is %s " % (self.name, arp_reply[ARP].hwsrc)) self._local_mac = arp_reply[ARP].hwsrc else: self.test.logger.info("No ARP received on port %s" % pg_interface.name) except: self.test.logger.error( ppp("Unexpected response to ARP request:", arp_reply)) raise def resolve_ndp(self, pg_interface=None): """Resolve NDP using provided packet-generator interface :param pg_interface: interface used to resolve, if None then this interface is used """ if pg_interface is None: pg_interface = self self.test.logger.info("Sending NDP request for %s on port %s" % (self.local_ip6, pg_interface.name)) ndp_req = self.create_ndp_req() pg_interface.add_stream(ndp_req) pg_interface.enable_capture() self.test.pg_start() self.test.logger.info(self.test.vapi.cli("show trace")) replies = pg_interface.get_capture(filter_fn=None) if replies is None or len(replies) == 0: self.test.logger.info("No NDP received on port %s" % pg_interface.name) return # Enabling IPv6 on an interface can generate more than the # ND reply we are looking for (namely MLD). So loop through # the replies to look for want we want. for ndp_reply in replies: # Make Dot1AD packet content recognizable to scapy if ndp_reply.type == 0x88a8: ndp_reply.type = 0x8100 ndp_reply = Ether(str(ndp_reply)) try: ndp_na = ndp_reply[ICMPv6ND_NA] opt = ndp_na[ICMPv6NDOptDstLLAddr] self.test.logger.info("VPP %s MAC address is %s " % (self.name, opt.lladdr)) self._local_mac = opt.lladdr except: self.test.logger.info( ppp("Unexpected response to NDP request:", ndp_reply)) # if no packets above provided the local MAC, then this failed. if not hasattr(self, '_local_mac'): raise
class VppPGInterface(VppInterface): """ VPP packet-generator interface """ @property def pg_index(self): """packet-generator interface index assigned by VPP""" return self._pg_index @property def out_path(self): """pcap file path - captured packets""" return self._out_path @property def in_path(self): """ pcap file path - injected packets""" return self._in_path @property def capture_cli(self): """CLI string to start capture on this interface""" return self._capture_cli @property def cap_name(self): """capture name for this interface""" return self._cap_name @property def input_cli(self): """CLI string to load the injected packets""" return self._input_cli @property def in_history_counter(self): """Self-incrementing counter used when renaming old pcap files""" v = self._in_history_counter self._in_history_counter += 1 return v @property def out_history_counter(self): """Self-incrementing counter used when renaming old pcap files""" v = self._out_history_counter self._out_history_counter += 1 return v def __init__(self, test, pg_index): """ Create VPP packet-generator interface """ r = test.vapi.pg_create_interface(pg_index) self._sw_if_index = r.sw_if_index super(VppPGInterface, self).__init__(test) self._in_history_counter = 0 self._out_history_counter = 0 self._pg_index = pg_index self._out_file = "pg%u_out.pcap" % self.pg_index self._out_path = self.test.tempdir + "/" + self._out_file self._in_file = "pg%u_in.pcap" % self.pg_index self._in_path = self.test.tempdir + "/" + self._in_file self._capture_cli = "packet-generator capture pg%u pcap %s" % ( self.pg_index, self.out_path) self._cap_name = "pcap%u" % self.sw_if_index self._input_cli = "packet-generator new pcap %s source pg%u name %s" % ( self.in_path, self.pg_index, self.cap_name) def enable_capture(self): """ Enable capture on this packet-generator interface""" try: if os.path.isfile(self.out_path): os.rename( self.out_path, "%s/history.[timestamp:%f].[%s-counter:%04d].%s" % (self.test.tempdir, time.time(), self.name, self.out_history_counter, self._out_file)) except: pass # FIXME this should be an API, but no such exists atm self.test.vapi.cli(self.capture_cli) self._pcap_reader = None def add_stream(self, pkts): """ Add a stream of packets to this packet-generator :param pkts: iterable packets """ try: if os.path.isfile(self.in_path): os.rename( self.in_path, "%s/history.[timestamp:%f].[%s-counter:%04d].%s" % (self.test.tempdir, time.time(), self.name, self.in_history_counter, self._in_file)) except: pass wrpcap(self.in_path, pkts) self.test.register_capture(self.cap_name) # FIXME this should be an API, but no such exists atm self.test.vapi.cli(self.input_cli) def _get_capture(self, timeout, filter_out_fn=is_ipv6_misc): """ Helper method to get capture and filter it """ try: if not self.wait_for_capture_file(timeout): return None output = rdpcap(self.out_path) self.test.logger.debug("Capture has %s packets" % len(output.res)) except: self.test.logger.debug("Exception in scapy.rdpcap(%s): %s" % (self.out_path, format_exc())) return None before = len(output.res) if filter_out_fn: output.res = [p for p in output.res if not filter_out_fn(p)] removed = len(output.res) - before if removed: self.test.logger.debug( "Filtered out %s packets from capture (returning %s)" % (removed, len(output.res))) return output def get_capture(self, expected_count=None, remark=None, timeout=1, filter_out_fn=is_ipv6_misc): """ Get captured packets :param expected_count: expected number of packets to capture, if None, then self.test.packet_count_for_dst_pg_idx is used to lookup the expected count :param remark: remark printed into debug logs :param timeout: how long to wait for packets :param filter_out_fn: filter applied to each packet, packets for which the filter returns True are removed from capture :returns: iterable packets """ remaining_time = timeout capture = None name = self.name if remark is None else "%s (%s)" % (self.name, remark) based_on = "based on provided argument" if expected_count is None: expected_count = \ self.test.get_packet_count_for_if_idx(self.sw_if_index) based_on = "based on stored packet_infos" self.test.logger.debug("Expecting to capture %s(%s) packets on %s" % (expected_count, based_on, name)) if expected_count == 0: raise Exception( "Internal error, expected packet count for %s is 0!" % name) while remaining_time > 0: before = time.time() capture = self._get_capture(remaining_time, filter_out_fn) elapsed_time = time.time() - before if capture: if len(capture.res) == expected_count: # bingo, got the packets we expected return capture remaining_time -= elapsed_time if capture: raise Exception("Captured packets mismatch, captured %s packets, " "expected %s packets on %s" % (len(capture.res), expected_count, name)) else: raise Exception("No packets captured on %s" % name) def assert_nothing_captured(self, remark=None, filter_out_fn=is_ipv6_misc): """ Assert that nothing unfiltered was captured on interface :param remark: remark printed into debug logs :param filter_out_fn: filter applied to each packet, packets for which the filter returns True are removed from capture """ if os.path.isfile(self.out_path): try: capture = self.get_capture(0, remark=remark, filter_out_fn=filter_out_fn) if capture: if len(capture.res) == 0: # junk filtered out, we're good return self.test.logger.error( ppc("Unexpected packets captured:", capture)) except: pass if remark: raise AssertionError( "Non-empty capture file present for interface %s(%s)" % (self.name, remark)) else: raise AssertionError( "Non-empty capture file present for interface %s" % self.name) def wait_for_capture_file(self, timeout=1): """ Wait until pcap capture file appears :param timeout: How long to wait for the packet (default 1s) :returns: True/False if the file is present or appears within timeout """ limit = time.time() + timeout if not os.path.isfile(self.out_path): self.test.logger.debug("Waiting for capture file %s to appear, " "timeout is %ss" % (self.out_path, timeout)) else: self.test.logger.debug("Capture file %s already exists" % self.out_path) return True while time.time() < limit: if os.path.isfile(self.out_path): break time.sleep(0) # yield if os.path.isfile(self.out_path): self.test.logger.debug("Capture file appeared after %fs" % (time.time() - (limit - timeout))) else: self.test.logger.debug("Timeout - capture file still nowhere") return False return True def wait_for_packet(self, timeout, filter_out_fn=is_ipv6_misc): """ Wait for next packet captured with a timeout :param timeout: How long to wait for the packet :returns: Captured packet if no packet arrived within timeout :raises Exception: if no packet arrives within timeout """ deadline = time.time() + timeout if self._pcap_reader is None: if not self.wait_for_capture_file(timeout): raise Exception("Capture file %s did not appear within " "timeout" % self.out_path) while time.time() < deadline: try: self._pcap_reader = PcapReader(self.out_path) break except: self.test.logger.debug( "Exception in scapy.PcapReader(%s): " "%s" % (self.out_path, format_exc())) if not self._pcap_reader: raise Exception("Capture file %s did not appear within " "timeout" % self.out_path) self.test.logger.debug("Waiting for packet") while time.time() < deadline: p = self._pcap_reader.recv() if p is not None: if filter_out_fn is not None and filter_out_fn(p): self.test.logger.debug( "Packet received after %ss was filtered out" % (time.time() - (deadline - timeout))) else: self.test.logger.debug("Packet received after %fs" % (time.time() - (deadline - timeout))) return p time.sleep(0) # yield self.test.logger.debug("Timeout - no packets received") raise Exception("Packet didn't arrive within timeout") def create_arp_req(self): """Create ARP request applicable for this interface""" return (Ether(dst="ff:ff:ff:ff:ff:ff", src=self.remote_mac) / ARP(op=ARP.who_has, pdst=self.local_ip4, psrc=self.remote_ip4, hwsrc=self.remote_mac)) def create_ndp_req(self): """Create NDP - NS applicable for this interface""" return (Ether(dst="ff:ff:ff:ff:ff:ff", src=self.remote_mac) / IPv6(src=self.remote_ip6, dst=self.local_ip6) / ICMPv6ND_NS(tgt=self.local_ip6) / ICMPv6NDOptSrcLLAddr(lladdr=self.remote_mac)) def resolve_arp(self, pg_interface=None): """Resolve ARP using provided packet-generator interface :param pg_interface: interface used to resolve, if None then this interface is used """ if pg_interface is None: pg_interface = self self.test.logger.info("Sending ARP request for %s on port %s" % (self.local_ip4, pg_interface.name)) arp_req = self.create_arp_req() pg_interface.add_stream(arp_req) pg_interface.enable_capture() self.test.pg_start() self.test.logger.info(self.test.vapi.cli("show trace")) try: captured_packet = pg_interface.wait_for_packet(1) except: self.test.logger.info("No ARP received on port %s" % pg_interface.name) return arp_reply = captured_packet.copy() # keep original for exception # Make Dot1AD packet content recognizable to scapy if arp_reply.type == 0x88a8: arp_reply.type = 0x8100 arp_reply = Ether(str(arp_reply)) try: if arp_reply[ARP].op == ARP.is_at: self.test.logger.info("VPP %s MAC address is %s " % (self.name, arp_reply[ARP].hwsrc)) self._local_mac = arp_reply[ARP].hwsrc else: self.test.logger.info("No ARP received on port %s" % pg_interface.name) except: self.test.logger.error( ppp("Unexpected response to ARP request:", captured_packet)) raise def resolve_ndp(self, pg_interface=None, timeout=1): """Resolve NDP using provided packet-generator interface :param pg_interface: interface used to resolve, if None then this interface is used :param timeout: how long to wait for response before giving up """ if pg_interface is None: pg_interface = self self.test.logger.info("Sending NDP request for %s on port %s" % (self.local_ip6, pg_interface.name)) ndp_req = self.create_ndp_req() pg_interface.add_stream(ndp_req) pg_interface.enable_capture() self.test.pg_start() now = time.time() deadline = now + timeout # Enabling IPv6 on an interface can generate more than the # ND reply we are looking for (namely MLD). So loop through # the replies to look for want we want. while now < deadline: try: captured_packet = pg_interface.wait_for_packet( deadline - now, filter_out_fn=None) except: self.test.logger.error( "Timeout while waiting for NDP response") raise ndp_reply = captured_packet.copy() # keep original for exception # Make Dot1AD packet content recognizable to scapy if ndp_reply.type == 0x88a8: ndp_reply.type = 0x8100 ndp_reply = Ether(str(ndp_reply)) try: ndp_na = ndp_reply[ICMPv6ND_NA] opt = ndp_na[ICMPv6NDOptDstLLAddr] self.test.logger.info("VPP %s MAC address is %s " % (self.name, opt.lladdr)) self._local_mac = opt.lladdr self.test.logger.debug(self.test.vapi.cli("show trace")) # we now have the MAC we've been after return except: self.test.logger.info( ppp("Unexpected response to NDP request:", captured_packet)) now = time.time() self.test.logger.debug(self.test.vapi.cli("show trace")) raise Exception("Timeout while waiting for NDP response")
def sniff(count=0, store=1, offline=None, prn=None, lfilter=None, L2socket=None, timeout=None, *arg, **karg): """Sniff packets sniff([count=0,] [prn=None,] [store=1,] [offline=None,] [lfilter=None,] + L2ListenSocket args) -> list of packets count: number of packets to capture. 0 means infinity store: wether to store sniffed packets or discard them prn: function to apply to each packet. If something is returned, it is displayed. Ex: ex: prn = lambda x: x.summary() lfilter: python function applied to each packet to determine if further action may be done ex: lfilter = lambda x: x.haslayer(Padding) offline: pcap file to read packets from, instead of sniffing them timeout: stop sniffing after a given time (default: None) L2socket: use the provided L2socket """ c = 0 if offline is None: if L2socket is None: L2socket = conf.L2listen s = L2socket(type=ETH_P_ALL, *arg, **karg) else: s = PcapReader(offline) lst = [] if timeout is not None: stoptime = time.time() + timeout remain = None while 1: try: if timeout is not None: remain = stoptime - time.time() if remain <= 0: break try: p = s.recv(MTU) except PcapTimeoutElapsed: continue if p is None: break if lfilter and not lfilter(p): continue if store: lst.append(p) c += 1 if prn: r = prn(p) if r is not None: print(r) if count > 0 and c >= count: break except KeyboardInterrupt: break s.close() return plist.PacketList(lst, "Sniffed")