# SECUREAUTH LABS. Copyright 2018 SecureAuth Corporation. All rights reserved.
#
# This software is provided under under a slightly modified version
# of the Apache Software License. See the accompanying LICENSE file
# for more information.
#
import struct
import array
from impacket.ImpactPacket import Header
from impacket.IP6_Address import IP6_Address
from impacket.IP6_Extension_Headers import IP6_Extension_Header
from impacket import LOG
class IP6(Header):
#Ethertype value for IPv6
ethertype = 0x86DD
HEADER_SIZE = 40
IP_PROTOCOL_VERSION = 6
def __init__(self, buffer = None):
Header.__init__(self, IP6.HEADER_SIZE)
self.set_ip_v(IP6.IP_PROTOCOL_VERSION)
if (buffer):
self.load_header(buffer)
def contains(self, aHeader):
Header.contains(self, aHeader)
if isinstance(aHeader, IP6_Extension_Header):
self.set_next_header(aHeader.get_header_type())
def get_header_size(self):
return IP6.HEADER_SIZE
def __str__(self):
protocol_version = self.get_ip_v()
traffic_class = self.get_traffic_class()
flow_label = self.get_flow_label()
payload_length = self.get_payload_length()
next_header = self.get_next_header()
hop_limit = self.get_hop_limit()
source_address = self.get_ip_src()
destination_address = self.get_ip_dst()
s = "Protocol version: " + str(protocol_version) + "\n"
s += "Traffic class: " + str(traffic_class) + "\n"
s += "Flow label: " + str(flow_label) + "\n"
s += "Payload length: " + str(payload_length) + "\n"
s += "Next header: " + str(next_header) + "\n"
s += "Hop limit: " + str(hop_limit) + "\n"
s += "Source address: " + source_address.as_string() + "\n"
s += "Destination address: " + destination_address.as_string() + "\n"
return s
def get_pseudo_header(self):
source_address = self.get_ip_src().as_bytes()
#FIXME - Handle Routing header special case
destination_address = self.get_ip_dst().as_bytes()
reserved_bytes = [ 0x00, 0x00, 0x00 ]
upper_layer_packet_length = self.get_payload_length()
upper_layer_protocol_number = self.get_next_header()
next_header = self.child()
68 ↛ 71line 68 didn't jump to line 71, because the condition on line 68 was never true while isinstance(next_header, IP6_Extension_Header):
# The length used in the pseudo-header is the Payload Length from the IPv6 header, minus
# the length of any extension headers present between the IPv6 header and the upper-layer header
upper_layer_packet_length -= next_header.get_header_size()
# If there are extension headers, fetch the correct upper-player protocol number by traversing the list
upper_layer_protocol_number = next_header.get_next_header()
next_header = next_header.child()
pseudo_header = array.array('B')
pseudo_header.extend(source_address)
pseudo_header.extend(destination_address)
pseudo_header.fromstring(struct.pack('!L', upper_layer_packet_length))
pseudo_header.fromlist(reserved_bytes)
pseudo_header.fromstring(struct.pack('B', upper_layer_protocol_number))
return pseudo_header
############################################################################
def get_ip_v(self):
return (self.get_byte(0) & 0xF0) >> 4
def get_traffic_class(self):
return ((self.get_byte(0) & 0x0F) << 4) | ((self.get_byte(1) & 0xF0) >> 4)
def get_flow_label(self):
return (self.get_byte(1) & 0x0F) << 16 | (self.get_byte(2) << 8) | self.get_byte(3)
def get_payload_length(self):
return (self.get_byte(4) << 8) | self.get_byte(5)
def get_next_header(self):
return (self.get_byte(6))
def get_hop_limit(self):
return (self.get_byte(7))
def get_ip_src(self):
address = IP6_Address(self.get_bytes()[8:24])
return (address)
def get_ip_dst(self):
address = IP6_Address(self.get_bytes()[24:40])
return (address)
############################################################################
def set_ip_v(self, version):
115 ↛ 116line 115 didn't jump to line 116, because the condition on line 115 was never true if (version != 6):
raise Exception('set_ip_v - version != 6')
#Fetch byte, clear high nibble
b = self.get_byte(0) & 0x0F
#Store version number in high nibble
b |= (version << 4)
#Store byte in buffer
#This behaviour is repeated in the rest of the methods
self.set_byte(0, b)
def set_traffic_class(self, traffic_class):
b0 = self.get_byte(0) & 0xF0
b1 = self.get_byte(1) & 0x0F
b0 |= (traffic_class & 0xF0) >> 4
b1 |= (traffic_class & 0x0F) << 4
self.set_byte(0, b0)
self.set_byte(1, b1)
def set_flow_label(self, flow_label):
b1 = self.get_byte(1) & 0xF0
b1 |= (flow_label & 0xF0000) >> 16
self.set_byte(1, b1)
self.set_byte(2, (flow_label & 0x0FF00) >> 8)
self.set_byte(3, (flow_label & 0x000FF))
def set_payload_length(self, payload_length):
self.set_byte(4, (payload_length & 0xFF00) >> 8)
self.set_byte(5, (payload_length & 0x00FF))
def set_next_header(self, next_header):
self.set_byte(6, next_header)
def set_hop_limit(self, hop_limit):
self.set_byte(7, hop_limit)
def set_ip_src(self, source_address):
address = IP6_Address(source_address)
bytes = self.get_bytes()
bytes[8:24] = address.as_bytes()
self.set_bytes(bytes)
def set_ip_dst(self, destination_address):
address = IP6_Address(destination_address)
bytes = self.get_bytes()
bytes[24:40] = address.as_bytes()
self.set_bytes(bytes)
def get_protocol_version(self):
LOG.warning('deprecated soon')
return self.get_ip_v()
def get_source_address(self):
LOG.warning('deprecated soon')
return self.get_ip_src()
def get_destination_address(self):
LOG.warning('deprecated soon')
return self.get_ip_dst()
def set_protocol_version(self, version):
LOG.warning('deprecated soon')
self.set_ip_v(version)
def set_source_address(self, source_address):
LOG.warning('deprecated soon')
self.set_ip_src(source_address)
def set_destination_address(self, destination_address):
LOG.warning('deprecated soon')
self.set_ip_dst(destination_address)
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