diff options
Diffstat (limited to 'scripts/external_libs/scapy-python3-0.18/scapy/contrib/carp.py')
-rw-r--r-- | scripts/external_libs/scapy-python3-0.18/scapy/contrib/carp.py | 65 |
1 files changed, 65 insertions, 0 deletions
diff --git a/scripts/external_libs/scapy-python3-0.18/scapy/contrib/carp.py b/scripts/external_libs/scapy-python3-0.18/scapy/contrib/carp.py new file mode 100644 index 00000000..e785adef --- /dev/null +++ b/scripts/external_libs/scapy-python3-0.18/scapy/contrib/carp.py @@ -0,0 +1,65 @@ + +# scapy.contrib.description = CARP +# scapy.contrib.status = loads + +from scapy.packet import * +from scapy.layers.inet import IP +from scapy.fields import BitField, ByteField, XShortField, IntField, XIntField +from scapy.utils import checksum +import struct, hmac, hashlib + +class CARP(Packet): + name = "CARP" + fields_desc = [ BitField("version", 4, 4), + BitField("type", 4, 4), + ByteField("vhid", 1), + ByteField("advskew", 0), + ByteField("authlen", 0), + ByteField("demotion", 0), + ByteField("advbase", 0), + XShortField("chksum", 0), + XIntField("counter1", 0), + XIntField("counter2", 0), + XIntField("hmac1", 0), + XIntField("hmac2", 0), + XIntField("hmac3", 0), + XIntField("hmac4", 0), + XIntField("hmac5", 0) + ] + + def post_build(self, pkt, pay): + if self.chksum == None: + pkt = pkt[:6] + struct.pack("!H", checksum(pkt)) + pkt[8:] + + return pkt + +def build_hmac_sha1(pkt, pw = '\0' * 20, ip4l = [], ip6l = []): + if not pkt.haslayer(CARP): + return None + + p = pkt[CARP] + h = hmac.new(pw, digestmod = hashlib.sha1) + # XXX: this is a dirty hack. it needs to pack version and type into a single 8bit field + h.update('\x21') + # XXX: mac addy if different from special link layer. comes before vhid + h.update(struct.pack('!B', p.vhid)) + + sl = [] + for i in ip4l: + # sort ips from smallest to largest + sl.append(inet_aton(i)) + sl.sort() + + for i in sl: + h.update(i) + + # XXX: do ip6l sorting + + return h.digest() + +""" +XXX: Usually CARP is multicast to 224.0.0.18 but because of virtual setup, it'll +be unicast between nodes. Uncomment the following line for normal use +bind_layers(IP, CARP, proto=112, dst='224.0.0.18') +""" +bind_layers(IP, CARP, proto=112) |