diff options
Diffstat (limited to 'test/util.py')
| -rw-r--r-- | test/util.py | 195 |
1 files changed, 185 insertions, 10 deletions
diff --git a/test/util.py b/test/util.py index 3e0267a3f4d..512bf9e3b7e 100644 --- a/test/util.py +++ b/test/util.py @@ -8,10 +8,10 @@ from scapy.layers.inet6 import in6_mactoifaceid from scapy.layers.l2 import Ether from scapy.packet import Raw -from scapy.layers.inet import IP, UDP, TCP -from scapy.layers.inet6 import IPv6, ICMPv6Unknown, ICMPv6EchoRequest -from scapy.packet import Packet -from socket import inet_pton, AF_INET, AF_INET6 +from scapy.layers.inet import IP +from scapy.layers.inet6 import IPv6, IPv6ExtHdrFragment, IPv6ExtHdrRouting,\ + IPv6ExtHdrHopByHop +from socket import AF_INET6 def ppp(headline, packet): @@ -37,8 +37,7 @@ def ppc(headline, capture, limit=10): 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) @@ -174,6 +173,7 @@ class ForeignAddressFactory(object): 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] @@ -189,7 +189,7 @@ class L4_Conn(): def pkt(self, side, l4args={}, payload="x"): is_ip6 = 1 if self.address_family == AF_INET6 else 0 s0 = side - s1 = 1-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), @@ -208,7 +208,7 @@ class L4_Conn(): l4args['flags'] = flags self.ifs[side].add_stream(self.pkt(side, l4args=l4args, payload=payload)) - self.ifs[1-side].enable_capture() + self.ifs[1 - side].enable_capture() self.testcase.pg_start() def recv(self, side): @@ -217,15 +217,190 @@ class L4_Conn(): def send_through(self, side, flags=None, payload=""): self.send(side, flags, payload) - p = self.recv(1-side) + 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) + 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 |