# Copyright (c) 2005, Neville-Neil Consulting # All rights reserved. # # Redistribution and use in source and binary forms, with or without # modification, are permitted provided that the following conditions are # met: # # Redistributions of source code must retain the above copyright notice, # this list of conditions and the following disclaimer. # # Redistributions in binary form must reproduce the above copyright # notice, this list of conditions and the following disclaimer in the # documentation and/or other materials provided with the distribution. # # Neither the name of Neville-Neil Consulting nor the names of its # contributors may be used to endorse or promote products derived from # this software without specific prior written permission. # # THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS # "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT # LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR # A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT # OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, # SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT # LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, # DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY # THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT # (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE # OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. # # File: $Id: icmpv6.py,v 1.8 2006/08/30 02:10:40 gnn Exp $ # # Author: George V. Neville-Neil # # Description: A class which describes an ICMPv6 packet import pcs import struct import pseudoipv6 # icmp6 type ND_ROUTER_SOLICIT = 133 ND_ROUTER_ADVERT = 134 ND_NEIGHBOR_SOLICIT = 135 ND_NEIGHBOR_ADVERT = 136 ND_REDIRECT = 137 MLD6_LISTENER_QUERY = 130 MLD6_LISTENER_REPORT = 131 MLD6_LISTENER_DONE = 132 MLD6_MTRACE_RESP = 200 MLD6_MTRACE = 201 ICMP6_ROUTER_RENUMBERING = 138 ICMP6_NI_QUERY = 139 ICMP6_NI_REPLY = 140 ICMP6_WRUREQUEST = 139 ICMP6_WRUREPLY = 140 ICMP6_DST_UNREACH = 1 ICMP6_PACKET_TOO_BIG = 2 ICMP6_TIME_EXCEEDED = 3 ICMP6_PARAM_PROB = 4 ICMP6_ECHO_REQUEST = 128 ICMP6_ECHO_REPLY = 129 # router renumbering flags ICMP6_RR_FLAGS_TEST = 0x80 ICMP6_RR_FLAGS_REQRESULT = 0x40 ICMP6_RR_FLAGS_FORCEAPPLY = 0x20 ICMP6_RR_FLAGS_SPECSITE = 0x10 ICMP6_RR_FLAGS_PREVDONE = 0x08 class icmpv6(pcs.Packet): layout = pcs.Layout() def __init__(self, type = 0, bytes = None): """icmpv6 header RFC2463 and RFC2461""" ty = pcs.Field("type", 8, default = type) code = pcs.Field("code", 8) cksum = pcs.Field("checksum", 16) if type == ICMP6_ECHO_REQUEST or type == ICMP6_ECHO_REPLY: id = pcs.Field("id", 16) seq = pcs.Field("sequence", 16) pcs.Packet.__init__(self, [ty, code, cksum, id, seq], bytes) elif type == ICMP6_TIME_EXCEEDED or type == ICMP6_DST_UNREACH or type == ND_ROUTER_SOLICIT: unused = pcs.Field("unused", 32) pcs.Packet.__init__(self, [ty, code, cksum, unused], bytes) elif type == ICMP6_PARAM_PROB: pointer = pcs.Field("pointer", 32) pcs.Packet.__init__(self, [ty, code, cksum, pointer], bytes) elif type == ICMP6_PACKET_TOO_BIG: mtu = pcs.Field("mtu", 32) pcs.Packet.__init__(self, [ty, code, cksum, mtu], bytes) elif type == ICMP6_NI_QUERY or type == ICMP6_NI_REPLY: qtype = pcs.Field("qtype", 16) flags = pcs.Field("flags", 16) nonce = pcs.Field("nonce", 64) pcs.Packet.__init__(self, [ty, code, cksum, qtype, flags, nonce], bytes) elif type == ND_ROUTER_ADVERT: chp = pcs.Field("current_hop_limit", 8) m = pcs.Field("m", 1) o = pcs.Field("o", 1) unused = pcs.Field("unused", 6) rlf = pcs.Field("router_lifetime", 16) rct = pcs.Field("reachable_time", 32) rtt = pcs.Field("retrans_timer", 32) pcs.Packet.__init__(self, [ty, code, cksum, chp, m, o, unused, rlf, rct, rtt], bytes) elif type == ND_NEIGHBOR_SOLICIT: reserved = pcs.Field("reserved", 32) target = pcs.StringField("target", 16 * 8) pcs.Packet.__init__(self, [ty, code, cksum, reserved, target], bytes) elif type == ND_NEIGHBOR_ADVERT: r = pcs.Field("router", 1) s = pcs.Field("solicited", 1) o = pcs.Field("override", 1) reserved = pcs.Field("reserved", 29) target = pcs.StringField("target", 16 * 8) pcs.Packet.__init__(self, [ty, code, cksum, r, s, o, reserved, target], bytes) elif type == ND_REDIRECT: reserved = pcs.Field("reserved", 32) target = pcs.StringField("target", 16 * 8) dest = pcs.StringField("destination", 16 * 8) pcs.Packet.__init__(self, [ty, code, cksum, reserved, target, dest], bytes) elif type == MLD6_LISTENER_QUERY or type == MLD6_LISTENER_REPORT or type == MLD6_LISTENER_DONE: md = pcs.Field("maxdelay", 16) reserved = pcs.Field("reserved", 16) mcast = pcs.StringField("mcastaddr", 16 * 8) pcs.Packet.__init__(self, [ty, code, cksum, md, reserved, mcast], bytes) else: pcs.Packet.__init__(self, [ty, code, cksum], bytes) def cksum(self, ip, data = "", nx = 0): """return icmpv6 checksum if we send packet through raw link level (i.e bpf)""" total = 0 p6 = pseudoipv6.pseudoipv6() p6.src = ip.src p6.dst = ip.dst p6.length = len(self.getbytes()) + len (data) if nx: p6.next_header = nx else: p6.next_header = ip.next_header pkt = p6.getbytes() + self.getbytes() + data if len(pkt) % 2 == 1: pkt += "\0" for i in range(len(pkt)/2): total += (struct.unpack("!H", pkt[2*i:2*i+2])[0]) total = (total >> 16) + (total & 0xffff) total += total >> 16 return ~total class icmpv6option(pcs.Packet): layout = pcs.Layout() def __init__(self, type = 0, bytes = None): """add icmp6 option header RFC2461""" ty = pcs.Field("type", 8, default = type) length = pcs.Field("length", 8) # Source Link-Layer Address. if type == 1: source = pcs.Field("source", 48) pcs.Packet.__init__(self, [ty, length, source], bytes) # Target Link-Layer Address elif type == 2: target = pcs.Field("target", 48) pcs.Packet.__init__(self, [ty, length, target], bytes) # Prefix Information. elif type == 3: plength = pcs.Field("prefix_length", 8) l = pcs.Field("L", 1) a = pcs.Field("A", 1) reserved1 = pcs.Field("reserved1", 6) vlf = pcs.Field("valid_lifetime", 32) plf = pcs.Field("preferred_lifetime", 32) reserved2 = pcs.Field("reserved2", 32) prefix = pcs.Field("prefix", 16 * 8, type = str) pcs.Packet.__init__(self, [ty, length, plength, l, a, reserved1, vlf, plf, reserved2, prefix], bytes) # Redirected Header. elif type == 4: reserved = pcs.Field("reserved", 48) pcs.Packet.__init__(self, [ty, length, reserved], bytes) # MTU elif type == 5: reserved = pcs.Field("reserved", 16) mtu = pcs.Field("mtu", 32) pcs.Packet.__init__(self, [ty, length, reserved, mtu], bytes) else: pcs.Packet.__init__(self, [ty, length], bytes)