metasploit-framework/lib/packetfu/arp.rb

240 lines
7.4 KiB
Ruby

module PacketFu
# ARPHeader is a complete ARP struct, used in ARPPacket.
#
# ARP is used to discover the machine address of nearby devices.
#
# See http://www.networksorcery.com/enp/protocol/arp.htm for details.
#
# ==== Header Definition
#
# Int16 :arp_hw Default: 1 # Ethernet
# Int16 :arp_proto, Default: 0x8000 # IP
# Int8 :arp_hw_len, Default: 6
# Int8 :arp_proto_len, Default: 4
# Int16 :arp_opcode, Default: 1 # 1: Request, 2: Reply, 3: Request-Reverse, 4: Reply-Reverse
# EthMac :arp_src_mac # From eth.rb
# Octets :arp_src_ip # From ip.rb
# EthMac :arp_dst_mac # From eth.rb
# Octets :arp_dst_ip # From ip.rb
# String :body
class ARPHeader < Struct.new(:arp_hw, :arp_proto, :arp_hw_len,
:arp_proto_len, :arp_opcode,
:arp_src_mac, :arp_src_ip,
:arp_dst_mac, :arp_dst_ip,
:body)
include StructFu
def initialize(args={})
super(
Int16.new(args[:arp_hw] || 1),
Int16.new(args[:arp_proto] ||0x0800),
Int8.new(args[:arp_hw_len] || 6),
Int8.new(args[:arp_proto_len] || 4),
Int16.new(args[:arp_opcode] || 1),
EthMac.new.read(args[:arp_src_mac]),
Octets.new.read(args[:arp_src_ip]),
EthMac.new.read(args[:arp_dst_mac]),
Octets.new.read(args[:arp_dst_ip]),
StructFu::String.new.read(args[:body])
)
end
# Returns the object in string form.
def to_s
self.to_a.map {|x| x.to_s}.join
end
# Reads a string to populate the object.
def read(str)
force_binary(str)
return self if str.nil?
self[:arp_hw].read(str[0,2])
self[:arp_proto].read(str[2,2])
self[:arp_hw_len].read(str[4,1])
self[:arp_proto_len].read(str[5,1])
self[:arp_opcode].read(str[6,2])
self[:arp_src_mac].read(str[8,6])
self[:arp_src_ip].read(str[14,4])
self[:arp_dst_mac].read(str[18,6])
self[:arp_dst_ip].read(str[24,4])
self[:body].read(str[28,str.size])
self
end
# Setter for the ARP hardware type.
def arp_hw=(i); typecast i; end
# Getter for the ARP hardware type.
def arp_hw; self[:arp_hw].to_i; end
# Setter for the ARP protocol.
def arp_proto=(i); typecast i; end
# Getter for the ARP protocol.
def arp_proto; self[:arp_proto].to_i; end
# Setter for the ARP hardware type length.
def arp_hw_len=(i); typecast i; end
# Getter for the ARP hardware type length.
def arp_hw_len; self[:arp_hw_len].to_i; end
# Setter for the ARP protocol length.
def arp_proto_len=(i); typecast i; end
# Getter for the ARP protocol length.
def arp_proto; self[:arp_proto].to_i; end
# Setter for the ARP opcode.
def arp_opcode=(i); typecast i; end
# Getter for the ARP opcode.
def arp_opcode; self[:arp_opcode].to_i; end
# Setter for the ARP source MAC address.
def arp_src_mac=(i); typecast i; end
# Getter for the ARP source MAC address.
def arp_src_mac; self[:arp_src_mac].to_s; end
# Getter for the ARP source IP address.
def arp_src_ip=(i); typecast i; end
# Setter for the ARP source IP address.
def arp_src_ip; self[:arp_src_ip].to_s; end
# Setter for the ARP destination MAC address.
def arp_dst_mac=(i); typecast i; end
# Setter for the ARP destination MAC address.
def arp_dst_mac; self[:arp_dst_mac].to_s; end
# Setter for the ARP destination IP address.
def arp_dst_ip=(i); typecast i; end
# Getter for the ARP destination IP address.
def arp_dst_ip; self[:arp_dst_ip].to_s; end
# Set the source MAC address in a more readable way.
def arp_saddr_mac=(mac)
mac = EthHeader.mac2str(mac)
self[:arp_src_mac].read(mac)
self.arp_src_mac
end
# Get a more readable source MAC address.
def arp_saddr_mac
EthHeader.str2mac(self[:arp_src_mac].to_s)
end
# Set the destination MAC address in a more readable way.
def arp_daddr_mac=(mac)
mac = EthHeader.mac2str(mac)
self[:arp_dst_mac].read(mac)
self.arp_dst_mac
end
# Get a more readable source MAC address.
def arp_daddr_mac
EthHeader.str2mac(self[:arp_dst_mac].to_s)
end
# Set a more readable source IP address.
def arp_saddr_ip=(addr)
self[:arp_src_ip].read_quad(addr)
end
# Get a more readable source IP address.
def arp_saddr_ip
self[:arp_src_ip].to_x
end
# Set a more readable destination IP address.
def arp_daddr_ip=(addr)
self[:arp_dst_ip].read_quad(addr)
end
# Get a more readable destination IP address.
def arp_daddr_ip
self[:arp_dst_ip].to_x
end
end # class ARPHeader
# ARPPacket is used to construct ARP packets. They contain an EthHeader and an ARPHeader.
# == Example
#
# require 'packetfu'
# arp_pkt = PacketFu::ARPPacket.new(:flavor => "Windows")
# arp_pkt.arp_saddr_mac="00:1c:23:44:55:66" # Your hardware address
# arp_pkt.arp_saddr_ip="10.10.10.17" # Your IP address
# arp_pkt.arp_daddr_ip="10.10.10.1" # Target IP address
# arp_pkt.arp_opcode=1 # Request
#
# arp_pkt.to_w('eth0') # Inject on the wire. (requires root)
# arp_pkt.to_f('/tmp/arp.pcap') # Write to a file.
#
# == Parameters
#
# :flavor
# Sets the "flavor" of the ARP packet. Choices are currently:
# :windows, :linux, :hp_deskjet
# :eth
# A pre-generated EthHeader object. If not specified, a new one will be created.
# :arp
# A pre-generated ARPHeader object. If not specificed, a new one will be created.
# :config
# A hash of return address details, often the output of Utils.whoami?
class ARPPacket < Packet
attr_accessor :eth_header, :arp_header
def initialize(args={})
@eth_header = EthHeader.new(args).read(args[:eth])
@arp_header = ARPHeader.new(args).read(args[:arp])
@eth_header.eth_proto = "\x08\x06"
@eth_header.body=@arp_header
# Please send more flavors to todb-packetfu@planb-security.net.
# Most of these initial fingerprints come from one (1) sample.
case (args[:flavor].nil?) ? :nil : args[:flavor].to_s.downcase.intern
when :windows; @arp_header.body = "\x00" * 64 # 64 bytes of padding
when :linux; @arp_header.body = "\x00" * 4 + # 32 bytes of padding
"\x00\x07\x5c\x14" + "\x00" * 4 +
"\x00\x0f\x83\x34" + "\x00\x0f\x83\x74" +
"\x01\x11\x83\x78" + "\x00\x00\x00\x0c" +
"\x00\x00\x00\x00"
when :hp_deskjet; # Pads up to 60 bytes.
@arp_header.body = "\xe0\x90\x0d\x6c" +
"\xff\xff\xee\xee" + "\x00" * 4 +
"\xe0\x8f\xfa\x18\x00\x20"
else; @arp_header.body = "\x00" * 18 # Pads up to 60 bytes.
end
@headers = [@eth_header, @arp_header]
super
end
# Generates summary data for ARP packets.
def peek(args={})
peek_data = ["A "]
peek_data << "%-5d" % self.to_s.size
peek_data << arp_saddr_mac
peek_data << "(#{arp_saddr_ip})"
peek_data << "->"
peek_data << case arp_daddr_mac
when "00:00:00:00:00:00"; "Bcast00"
when "ff:ff:ff:ff:ff:ff"; "BcastFF"
else; arp_daddr_mac
end
peek_data << "(#{arp_daddr_ip})"
peek_data << ":"
peek_data << case arp_opcode
when 1; "Requ"
when 2; "Repl"
when 3; "RReq"
when 4; "RRpl"
when 5; "IReq"
when 6; "IRpl"
else; "0x%02x" % arp_opcode
end
peek_data.join
end
# While there are lengths in ARPPackets, there's not
# much to do with them.
def recalc(args={})
@headers[0].inspect
end
end
end
# vim: nowrap sw=2 sts=0 ts=2 ff=unix ft=ruby