import socket
import sys
+import os.path
from abc import abstractmethod, ABCMeta
-from cStringIO import StringIO
+from scapy.utils6 import in6_mactoifaceid
+
+from scapy.layers.l2 import Ether
+from scapy.packet import Raw
+from scapy.layers.inet import IP
+from scapy.layers.inet6 import IPv6, IPv6ExtHdrFragment, IPv6ExtHdrRouting,\
+ IPv6ExtHdrHopByHop
+from scapy.utils import hexdump
+from socket import AF_INET6
+from io import BytesIO
+from vpp_papi import mac_pton
def ppp(headline, packet):
""" Return string containing the output of scapy packet.show() call. """
- o = StringIO()
+ o = BytesIO()
old_stdout = sys.stdout
sys.stdout = o
print(headline)
+ hexdump(packet)
+ print("")
packet.show()
sys.stdout = old_stdout
return o.getvalue()
tail = ""
if limit < len(capture):
tail = "\nPrint limit reached, %s out of %s packets printed" % (
- len(capture), limit)
- limit = len(capture)
+ limit, len(capture))
body = "".join([ppp("Packet #%s:" % count, p)
for count, p in zip(range(0, limit), capture)])
return "%s\n%s%s" % (headline, body, tail)
for ip in ip4_range(ip4, s, e))
+def mk_ll_addr(mac):
+ euid = in6_mactoifaceid(mac)
+ addr = "fe80::" + euid
+ return addr
+
+
+def ip6_normalize(ip6):
+ return socket.inet_ntop(socket.AF_INET6,
+ socket.inet_pton(socket.AF_INET6, ip6))
+
+
+def get_core_path(tempdir):
+ return "%s/%s" % (tempdir, get_core_pattern())
+
+
+def is_core_present(tempdir):
+ return os.path.isfile(get_core_path(tempdir))
+
+
+def get_core_pattern():
+ with open("/proc/sys/kernel/core_pattern", "r") as f:
+ corefmt = f.read().strip()
+ return corefmt
+
+
+def check_core_path(logger, core_path):
+ corefmt = get_core_pattern()
+ if corefmt.startswith("|"):
+ logger.error(
+ "WARNING: redirecting the core dump through a"
+ " filter may result in truncated dumps.")
+ logger.error(
+ " You may want to check the filter settings"
+ " or uninstall it and edit the"
+ " /proc/sys/kernel/core_pattern accordingly.")
+ logger.error(
+ " current core pattern is: %s" % corefmt)
+
+
class NumericConstant(object):
__metaclass__ = ABCMeta
""" MAC address """
return self._mac
+ @property
+ def bin_mac(self):
+ """ MAC address """
+ return mac_pton(self._mac)
+
@property
def ip4(self):
""" IPv4 address - string """
""" IPv6 address of remote host - raw, suitable as API parameter."""
return socket.inet_pton(socket.AF_INET6, self._ip6)
- def __init__(self, mac=None, ip4=None, ip6=None):
+ @property
+ def ip6_ll(self):
+ """ IPv6 link-local address - string """
+ return self._ip6_ll
+
+ @property
+ def ip6n_ll(self):
+ """ IPv6 link-local address of remote host -
+ raw, suitable as API parameter."""
+ return socket.inet_pton(socket.AF_INET6, self._ip6_ll)
+
+ def __eq__(self, other):
+ if isinstance(other, Host):
+ return (self.mac == other.mac and
+ self.ip4 == other.ip4 and
+ self.ip6 == other.ip6 and
+ self.ip6_ll == other.ip6_ll)
+ else:
+ return False
+
+ def __ne__(self, other):
+ return not self.__eq__(other)
+
+ def __repr__(self):
+ return "Host { mac:%s ip4:%s ip6:%s ip6_ll:%s }" % (self.mac,
+ self.ip4,
+ self.ip6,
+ self.ip6_ll)
+
+ def __hash__(self):
+ return hash(self.__repr__())
+
+ def __init__(self, mac=None, ip4=None, ip6=None, ip6_ll=None):
self._mac = mac
self._ip4 = ip4
self._ip6 = ip6
+ self._ip6_ll = ip6_ll
+
+
+class ForeignAddressFactory(object):
+ count = 0
+ prefix_len = 24
+ net_template = '10.10.10.{}'
+ net = net_template.format(0) + '/' + str(prefix_len)
+
+ def get_ip4(self):
+ if self.count > 255:
+ raise Exception("Network host address exhaustion")
+ self.count += 1
+ return self.net_template.format(self.count)
+
+
+class L4_Conn():
+ """ L4 'connection' tied to two VPP interfaces """
+
+ def __init__(self, testcase, if1, if2, af, l4proto, port1, port2):
+ self.testcase = testcase
+ self.ifs = [None, None]
+ self.ifs[0] = if1
+ self.ifs[1] = if2
+ self.address_family = af
+ self.l4proto = l4proto
+ self.ports = [None, None]
+ self.ports[0] = port1
+ self.ports[1] = port2
+ self
+
+ def pkt(self, side, l4args={}, payload="x"):
+ is_ip6 = 1 if self.address_family == AF_INET6 else 0
+ s0 = side
+ s1 = 1 - side
+ src_if = self.ifs[s0]
+ dst_if = self.ifs[s1]
+ layer_3 = [IP(src=src_if.remote_ip4, dst=dst_if.remote_ip4),
+ IPv6(src=src_if.remote_ip6, dst=dst_if.remote_ip6)]
+ merged_l4args = {'sport': self.ports[s0], 'dport': self.ports[s1]}
+ merged_l4args.update(l4args)
+ p = (Ether(dst=src_if.local_mac, src=src_if.remote_mac) /
+ layer_3[is_ip6] /
+ self.l4proto(**merged_l4args) /
+ Raw(payload))
+ return p
+
+ def send(self, side, flags=None, payload=""):
+ l4args = {}
+ if flags is not None:
+ l4args['flags'] = flags
+ self.ifs[side].add_stream(self.pkt(side,
+ l4args=l4args, payload=payload))
+ self.ifs[1 - side].enable_capture()
+ self.testcase.pg_start()
+
+ def recv(self, side):
+ p = self.ifs[side].wait_for_packet(1)
+ return p
+
+ def send_through(self, side, flags=None, payload=""):
+ self.send(side, flags, payload)
+ p = self.recv(1 - side)
+ return p
+
+ def send_pingpong(self, side, flags1=None, flags2=None):
+ p1 = self.send_through(side, flags1)
+ p2 = self.send_through(1 - side, flags2)
+ return [p1, p2]
+
+
+class L4_CONN_SIDE:
+ L4_CONN_SIDE_ZERO = 0
+ L4_CONN_SIDE_ONE = 1
+
+
+class LoggerWrapper(object):
+ def __init__(self, logger=None):
+ self._logger = logger
+
+ def debug(self, *args, **kwargs):
+ if self._logger:
+ self._logger.debug(*args, **kwargs)
+
+ def error(self, *args, **kwargs):
+ if self._logger:
+ self._logger.error(*args, **kwargs)
+
+
+def fragment_rfc791(packet, fragsize, _logger=None):
+ """
+ Fragment an IPv4 packet per RFC 791
+ :param packet: packet to fragment
+ :param fragsize: size at which to fragment
+ :note: IP options are not supported
+ :returns: list of fragments
+ """
+ logger = LoggerWrapper(_logger)
+ logger.debug(ppp("Fragmenting packet:", packet))
+ packet = packet.__class__(str(packet)) # recalculate all values
+ if len(packet[IP].options) > 0:
+ raise Exception("Not implemented")
+ if len(packet) <= fragsize:
+ return [packet]
+
+ pre_ip_len = len(packet) - len(packet[IP])
+ ip_header_len = packet[IP].ihl * 4
+ hex_packet = str(packet)
+ hex_headers = hex_packet[:(pre_ip_len + ip_header_len)]
+ hex_payload = hex_packet[(pre_ip_len + ip_header_len):]
+
+ pkts = []
+ ihl = packet[IP].ihl
+ otl = len(packet[IP])
+ nfb = (fragsize - pre_ip_len - ihl * 4) / 8
+ fo = packet[IP].frag
+
+ p = packet.__class__(hex_headers + hex_payload[:nfb * 8])
+ p[IP].flags = "MF"
+ p[IP].frag = fo
+ p[IP].len = ihl * 4 + nfb * 8
+ del p[IP].chksum
+ pkts.append(p)
+
+ p = packet.__class__(hex_headers + hex_payload[nfb * 8:])
+ p[IP].len = otl - nfb * 8
+ p[IP].frag = fo + nfb
+ del p[IP].chksum
+
+ more_fragments = fragment_rfc791(p, fragsize, _logger)
+ pkts.extend(more_fragments)
+
+ return pkts
+
+
+def fragment_rfc8200(packet, identification, fragsize, _logger=None):
+ """
+ Fragment an IPv6 packet per RFC 8200
+ :param packet: packet to fragment
+ :param fragsize: size at which to fragment
+ :note: IP options are not supported
+ :returns: list of fragments
+ """
+ logger = LoggerWrapper(_logger)
+ packet = packet.__class__(str(packet)) # recalculate all values
+ if len(packet) <= fragsize:
+ return [packet]
+ logger.debug(ppp("Fragmenting packet:", packet))
+ pkts = []
+ counter = 0
+ routing_hdr = None
+ hop_by_hop_hdr = None
+ upper_layer = None
+ seen_ipv6 = False
+ ipv6_nr = -1
+ l = packet.getlayer(counter)
+ while l is not None:
+ if l.__class__ is IPv6:
+ if seen_ipv6:
+ # ignore 2nd IPv6 header and everything below..
+ break
+ ipv6_nr = counter
+ seen_ipv6 = True
+ elif l.__class__ is IPv6ExtHdrFragment:
+ raise Exception("Already fragmented")
+ elif l.__class__ is IPv6ExtHdrRouting:
+ routing_hdr = counter
+ elif l.__class__ is IPv6ExtHdrHopByHop:
+ hop_by_hop_hdr = counter
+ elif seen_ipv6 and not upper_layer and \
+ not l.__class__.__name__.startswith('IPv6ExtHdr'):
+ upper_layer = counter
+ counter = counter + 1
+ l = packet.getlayer(counter)
+
+ logger.debug(
+ "Layers seen: IPv6(#%s), Routing(#%s), HopByHop(#%s), upper(#%s)" %
+ (ipv6_nr, routing_hdr, hop_by_hop_hdr, upper_layer))
+
+ if upper_layer is None:
+ raise Exception("Upper layer header not found in IPv6 packet")
+
+ last_per_fragment_hdr = ipv6_nr
+ if routing_hdr is None:
+ if hop_by_hop_hdr is not None:
+ last_per_fragment_hdr = hop_by_hop_hdr
+ else:
+ last_per_fragment_hdr = routing_hdr
+ logger.debug("Last per-fragment hdr is #%s" % (last_per_fragment_hdr))
+
+ per_fragment_headers = packet.copy()
+ per_fragment_headers[last_per_fragment_hdr].remove_payload()
+ logger.debug(ppp("Per-fragment headers:", per_fragment_headers))
+
+ ext_and_upper_layer = packet.getlayer(last_per_fragment_hdr)[1]
+ hex_payload = str(ext_and_upper_layer)
+ logger.debug("Payload length is %s" % len(hex_payload))
+ logger.debug(ppp("Ext and upper layer:", ext_and_upper_layer))
+
+ fragment_ext_hdr = IPv6ExtHdrFragment()
+ logger.debug(ppp("Fragment header:", fragment_ext_hdr))
+
+ if len(per_fragment_headers) + len(fragment_ext_hdr) +\
+ len(ext_and_upper_layer) - len(ext_and_upper_layer.payload)\
+ > fragsize:
+ raise Exception("Cannot fragment this packet - MTU too small "
+ "(%s, %s, %s, %s, %s)" % (
+ len(per_fragment_headers), len(fragment_ext_hdr),
+ len(ext_and_upper_layer),
+ len(ext_and_upper_layer.payload), fragsize))
+
+ orig_nh = packet[IPv6].nh
+ p = per_fragment_headers
+ del p[IPv6].plen
+ del p[IPv6].nh
+ p = p / fragment_ext_hdr
+ del p[IPv6ExtHdrFragment].nh
+ first_payload_len_nfb = (fragsize - len(p)) / 8
+ p = p / Raw(hex_payload[:first_payload_len_nfb * 8])
+ del p[IPv6].plen
+ p[IPv6ExtHdrFragment].nh = orig_nh
+ p[IPv6ExtHdrFragment].id = identification
+ p[IPv6ExtHdrFragment].offset = 0
+ p[IPv6ExtHdrFragment].m = 1
+ p = p.__class__(str(p))
+ logger.debug(ppp("Fragment %s:" % len(pkts), p))
+ pkts.append(p)
+ offset = first_payload_len_nfb * 8
+ logger.debug("Offset after first fragment: %s" % offset)
+ while len(hex_payload) > offset:
+ p = per_fragment_headers
+ del p[IPv6].plen
+ del p[IPv6].nh
+ p = p / fragment_ext_hdr
+ del p[IPv6ExtHdrFragment].nh
+ l_nfb = (fragsize - len(p)) / 8
+ p = p / Raw(hex_payload[offset:offset + l_nfb * 8])
+ p[IPv6ExtHdrFragment].nh = orig_nh
+ p[IPv6ExtHdrFragment].id = identification
+ p[IPv6ExtHdrFragment].offset = offset / 8
+ p[IPv6ExtHdrFragment].m = 1
+ p = p.__class__(str(p))
+ logger.debug(ppp("Fragment %s:" % len(pkts), p))
+ pkts.append(p)
+ offset = offset + l_nfb * 8
+
+ pkts[-1][IPv6ExtHdrFragment].m = 0 # reset more-flags in last fragment
+
+ return pkts
+
+
+def reassemble4_core(listoffragments, return_ip):
+ buffer = BytesIO()
+ first = listoffragments[0]
+ buffer.seek(20)
+ for pkt in listoffragments:
+ buffer.seek(pkt[IP].frag*8)
+ buffer.write(bytes(pkt[IP].payload))
+ first.len = len(buffer.getvalue()) + 20
+ first.flags = 0
+ del(first.chksum)
+ if return_ip:
+ header = bytes(first[IP])[:20]
+ return first[IP].__class__(header + buffer.getvalue())
+ else:
+ header = bytes(first[Ether])[:34]
+ return first[Ether].__class__(header + buffer.getvalue())
+
+
+def reassemble4_ether(listoffragments):
+ return reassemble4_core(listoffragments, False)
+
+
+def reassemble4(listoffragments):
+ return reassemble4_core(listoffragments, True)