metasploit-framework/lib/packetfu/eth.rb

265 lines
6.8 KiB
Ruby

module PacketFu
# EthOui is the Organizationally Unique Identifier portion of a MAC address, used in EthHeader.
#
# See the OUI list at http://standards.ieee.org/regauth/oui/oui.txt
#
# ==== Header Definition
#
# Fixnum :b0
# Fixnum :b1
# Fixnum :b2
# Fixnum :b3
# Fixnum :b4
# Fixnum :b5
# Fixnum :local
# Fixnum :multicast
# Int16 :oui, Default: 0x1ac5 :)
class EthOui < Struct.new(:b5, :b4, :b3, :b2, :b1, :b0, :local, :multicast, :oui)
# EthOui is unusual in that the bit values do not enjoy StructFu typing.
def initialize(args={})
args[:local] ||= 0
args[:oui] ||= 0x1ac # :)
args.each_pair {|k,v| args[k] = 0 unless v}
super(args[:b5], args[:b4], args[:b3], args[:b2],
args[:b1], args[:b0], args[:local], args[:multicast],
args[:oui])
end
# Returns the object in string form.
def to_s
byte = 0
byte += 0b10000000 if b5.to_i == 1
byte += 0b01000000 if b4.to_i == 1
byte += 0b00100000 if b3.to_i == 1
byte += 0b00010000 if b2.to_i == 1
byte += 0b00001000 if b1.to_i == 1
byte += 0b00000100 if b0.to_i == 1
byte += 0b00000010 if local.to_i == 1
byte += 0b00000001 if multicast.to_i == 1
[byte,oui].pack("Cn")
end
# Reads a string to populate the object.
def read(str)
force_binary(str)
return self if str.nil?
if 1.respond_to? :ord
byte = str[0].ord
else
byte = str[0]
end
self[:b5] = byte & 0b10000000 == 0b10000000 ? 1 : 0
self[:b4] = byte & 0b01000000 == 0b01000000 ? 1 : 0
self[:b3] = byte & 0b00100000 == 0b00100000 ? 1 : 0
self[:b2] = byte & 0b00010000 == 0b00010000 ? 1 : 0
self[:b1] = byte & 0b00001000 == 0b00001000 ? 1 : 0
self[:b0] = byte & 0b00000100 == 0b00000100 ? 1 : 0
self[:local] = byte & 0b00000010 == 0b00000010 ? 1 : 0
self[:multicast] = byte & 0b00000001 == 0b00000001 ? 1 : 0
self[:oui] = str[1,2].unpack("n").first
self
end
end
# EthNic is the Network Interface Controler portion of a MAC address, used in EthHeader.
#
# ==== Header Definition
#
# Fixnum :n1
# Fixnum :n2
# Fixnum :n3
#
class EthNic < Struct.new(:n0, :n1, :n2)
# EthNic does not enjoy StructFu typing.
def initialize(args={})
args.each_pair {|k,v| args[k] = 0 unless v}
super(args[:n0], args[:n1], args[:n2])
end
# Returns the object in string form.
def to_s
[n0,n1,n2].map {|x| x.to_i}.pack("C3")
end
# Reads a string to populate the object.
def read(str)
force_binary(str)
return self if str.nil?
self[:n0], self[:n1], self[:n2] = str[0,3].unpack("C3")
self
end
end
# EthMac is the combination of an EthOui and EthNic, used in EthHeader.
#
# ==== Header Definition
#
# EthOui :oui # See EthOui
# EthNic :nic # See EthNic
class EthMac < Struct.new(:oui, :nic)
def initialize(args={})
super(
EthOui.new.read(args[:oui]),
EthNic.new.read(args[:nic]))
end
# Returns the object in string form.
def to_s
"#{self[:oui]}#{self[:nic]}"
end
# Reads a string to populate the object.
def read(str)
force_binary(str)
return self if str.nil?
self.oui.read str[0,3]
self.nic.read str[3,3]
self
end
end
# EthHeader is a complete Ethernet struct, used in EthPacket.
# It's the base header for all other protocols, such as IPHeader,
# TCPHeader, etc.
#
# For more on the construction on MAC addresses, see
# http://en.wikipedia.org/wiki/MAC_address
#
# ==== Header Definition
#
# EthMac :eth_dst # See EthMac
# EthMac :eth_src # See EthMac
# Int16 :eth_proto, Default: 0x8000 # IP 0x0800, Arp 0x0806
# String :body
class EthHeader < Struct.new(:eth_dst, :eth_src, :eth_proto, :body)
include StructFu
def initialize(args={})
super(
EthMac.new.read(args[:eth_dst]),
EthMac.new.read(args[:eth_src]),
Int16.new(args[:eth_proto] || 0x0800),
StructFu::String.new.read(args[:body])
)
end
# Setter for the Ethernet destination address.
def eth_dst=(i); typecast(i); end
# Getter for the Ethernet destination address.
def eth_dst; self[:eth_dst].to_s; end
# Setter for the Ethernet source address.
def eth_src=(i); typecast(i); end
# Getter for the Ethernet source address.
def eth_src; self[:eth_src].to_s; end
# Setter for the Ethernet protocol number.
def eth_proto=(i); typecast(i); end
# Getter for the Ethernet protocol number.
def eth_proto; self[:eth_proto].to_i; 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[:eth_dst].read str[0,6]
self[:eth_src].read str[6,6]
self[:eth_proto].read str[12,2]
self[:body].read str[14,str.size]
self
end
# Converts a readable MAC (11:22:33:44:55:66) to a binary string.
# Readable MAC's may be split on colons, dots, spaces, or underscores.
#
# irb> PacketFu::EthHeader.mac2str("11:22:33:44:55:66")
#
# #=> "\021\"3DUf"
def self.mac2str(mac)
if mac.split(/[:\x2d\x2e\x5f]+/).size == 6
ret = mac.split(/[:\x2d\x2e\x20\x5f]+/).collect {|x| x.to_i(16)}.pack("C6")
else
raise ArgumentError, "Unkown format for mac address."
end
return ret
end
# Converts a binary string to a readable MAC (11:22:33:44:55:66).
#
# irb> PacketFu::EthHeader.str2mac("\x11\x22\x33\x44\x55\x66")
#
# #=> "11:22:33:44:55:66"
def self.str2mac(mac='')
if mac.to_s.size == 6 && mac.kind_of?(::String)
ret = mac.unpack("C6").map {|x| sprintf("%02x",x)}.join(":")
end
end
# Sets the source MAC address in a more readable way.
def eth_saddr=(mac)
mac = EthHeader.mac2str(mac)
self[:eth_src].read mac
self[:eth_src]
end
# Gets the source MAC address in a more readable way.
def eth_saddr
EthHeader.str2mac(self[:eth_src].to_s)
end
# Set the destination MAC address in a more readable way.
def eth_daddr=(mac)
mac = EthHeader.mac2str(mac)
self[:eth_dst].read mac
self[:eth_dst]
end
# Gets the destination MAC address in a more readable way.
def eth_daddr
EthHeader.str2mac(self[:eth_dst].to_s)
end
end
# EthPacket is used to construct Ethernet packets. They contain an
# Ethernet header, and that's about it.
#
# == Example
#
# require 'packetfu'
# eth_pkt = PacketFu::EthPacket.new
# eth_pkt.eth_saddr="00:1c:23:44:55:66"
# eth_pkt.eth_daddr="00:1c:24:aa:bb:cc"
#
# eth_pkt.to_w('eth0') # Inject on the wire. (require root)
class EthPacket < Packet
attr_accessor :eth_header
def initialize(args={})
@eth_header = EthHeader.new(args).read(args[:eth])
@headers = [@eth_header]
super
end
# Does nothing, really, since there's no length or
# checksum to calculate for a straight Ethernet packet.
def recalc(args={})
@headers[0].inspect
end
end
end
# vim: nowrap sw=2 sts=0 ts=2 ff=unix ft=ruby