Module: Msf::Exploit::Capture

Included in:
Auxiliary::NTP
Defined in:
lib/msf/core/exploit/capture.rb

Instance Attribute Summary collapse

Instance Method Summary collapse

Instance Attribute Details

#arp_cacheObject

Returns the value of attribute arp_cache.



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# File 'lib/msf/core/exploit/capture.rb', line 426

def arp_cache
  @arp_cache
end

#arp_captureObject

Returns the value of attribute arp_capture.



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# File 'lib/msf/core/exploit/capture.rb', line 426

def arp_capture
  @arp_capture
end

#captureObject

Returns the value of attribute capture.



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# File 'lib/msf/core/exploit/capture.rb', line 426

def capture
  @capture
end

#dst_cacheObject

Returns the value of attribute dst_cache.



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# File 'lib/msf/core/exploit/capture.rb', line 426

def dst_cache
  @dst_cache
end

Instance Method Details

#arp(target_ip = nil) ⇒ Object

A pure-Ruby ARP exchange. It uses self.arp_capture to send and recv packets, rather than self.capture.

Raises:

  • (RuntimeError)


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# File 'lib/msf/core/exploit/capture.rb', line 341

def arp(target_ip=nil)
  return self.arp_cache[target_ip] if self.arp_cache[target_ip]
  return self.arp_cache[:gateway] unless should_arp? target_ip
  source_ip = Rex::Socket.source_address(target_ip)
  raise RuntimeError, "Could not access the capture process." unless self.arp_capture

  p = arp_packet(target_ip, source_ip)

  # Try up to 3 times to get an ARP response
  1.upto(3) do
    inject_eth(:eth_type  => 0x0806,
      :payload   => p,
      :pcap      => self.arp_capture,
      :eth_saddr => self.arp_cache[Rex::Socket.source_address(target_ip)]
    )
    begin
      to = ((datastore['TIMEOUT'] || 500).to_f * 8) / 1000.0
      ::Timeout.timeout(to) do
        loop do
          my_packet = inject_reply(:arp, self.arp_capture)
          next unless my_packet
          next unless my_packet.arp_saddr_ip == target_ip
          self.arp_cache[target_ip] = my_packet.eth_saddr
          return self.arp_cache[target_ip]
        end
      end
    rescue ::Timeout::Error
    end
  end
  nil
end

#arp_packet(target_ip = nil, source_ip = nil) ⇒ Object

Creates a full ARP packet, mainly for use with inject_eth()



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# File 'lib/msf/core/exploit/capture.rb', line 374

def arp_packet(target_ip=nil, source_ip=nil)
  p               = PacketFu::ARPPacket.new
  p.arp_opcode    = 1
  p.arp_daddr_ip  = target_ip || datastore['RHOST']
  p.arp_saddr_ip  = source_ip || datastore['LHOST']
  my_eth          = self.arp_cache[Rex::Socket.source_address(target_ip)]
  p.arp_saddr_mac = my_eth || "00:00:00:00:00:00"
  return p
end

#capture_extract_ies(raw) ⇒ Object



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# File 'lib/msf/core/exploit/capture.rb', line 148

def capture_extract_ies(raw)
  set = {}
  idx = 0
  len = 0

  while (idx < raw.length)
    len = raw[idx+1]
    return set unless len
    set[raw[idx]] ||= []
    set[raw[idx]].push(raw[idx + 2, len])
    idx += len + 2
  end

  return set
end

#capture_icmp_echo_pack(id = nil, seq = nil, payload = nil) ⇒ Object

Intended to be used as the payload to an ICMP echo request’s payload



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# File 'lib/msf/core/exploit/capture.rb', line 561

def capture_icmp_echo_pack(id=nil, seq=nil, payload=nil)
  id  ||= rand(0x10000)
  seq ||= rand(0x10000)
  [id, seq, payload.to_s].pack("nna*")
end

#capture_icmp_echo_unpack(data) ⇒ Object

Decodes and ICMP echo request or response.



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# File 'lib/msf/core/exploit/capture.rb', line 568

def capture_icmp_echo_unpack(data)
  data.unpack("nna*")
end

#capture_sendto(payload = "", dhost = nil, bcast = false, dev = nil) ⇒ Object

Sends a payload to a given target using the pcap capture interface

Parameters:

payload

The payload String to send

dhost

the destination host to send to

bcast

set to ‘true` to send to the broadcast address if necessary

dev

the name of the network interface to send the payload on

Returns:

The number of bytes sent iff the payload was successfully sent/injected. ‘false` otherwise

Raises:

  • (RuntimeError)


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# File 'lib/msf/core/exploit/capture.rb', line 245

def capture_sendto(payload="", dhost=nil, bcast=false, dev=nil)
  raise RuntimeError, "Could not access the capture process (remember to open_pcap first!)" unless self.capture
  raise RuntimeError, "Must specify a host to sendto" unless dhost
  dev              ||= datastore['INTERFACE']
  dst_mac, src_mac = lookup_eth(dhost, dev)
  if dst_mac == nil and not bcast
    vprint_error("Unable to determine the destination MAC for #{dhost} on #{dev} and bcast is false")
    return false
  end
  inject_eth(:payload => payload, :eth_daddr => dst_mac, :eth_saddr => src_mac)
end

#check_pcaprub_loadedObject



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# File 'lib/msf/core/exploit/capture.rb', line 394

def check_pcaprub_loaded
  if not @pcaprub_loaded
    print_status("The Pcaprub module is not available: #{@pcaprub_error}")
    raise RuntimeError, "Pcaprub not available"
  elsif not @network_interface_loaded
    print_status("The NetworkInterface module is not available: #{@network_interface_error}")
    raise RuntimeError, "NetworkInterface not available"
  else
    true
  end
end

#close_pcapObject



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# File 'lib/msf/core/exploit/capture.rb', line 142

def close_pcap
  return unless self.capture
  self.capture     = nil
  self.arp_capture = nil
end

#each_packetObject

Loop through each packet



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# File 'lib/msf/core/exploit/capture.rb', line 167

def each_packet
  return unless capture
  @capture_count ||= 0
  capture.each do |pkt|
    yield(pkt)
    @capture_count += 1
  end
  @capture_count
end

#expire_arpcacheObject

Allow modules to reset their arp caches arbitrarily.



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# File 'lib/msf/core/exploit/capture.rb', line 385

def expire_arpcache
  self.arp_cache = {}
end

#get_interface_guid(dev) ⇒ Object

This function is useful only on windows where pcaprub use the GUID



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# File 'lib/msf/core/exploit/capture.rb', line 461

def get_interface_guid(dev)
  check_pcaprub_loaded
  if RUBY_PLATFORM == "i386-mingw32"
    if dev.to_s =~ /^[0-9]{1,2}$/
      if is_interface?(dev)
        NetworkInterface.interfaces[(dev.to_i) - 1]
      else
        return dev
      end
    else
      return dev
    end
  else #Non windows
    return dev
  end
end

#get_ipv4_addr(dev, num = 0) ⇒ Object

Raises:

  • (RuntimeError)


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# File 'lib/msf/core/exploit/capture.rb', line 495

def get_ipv4_addr(dev, num=0)
  check_pcaprub_loaded
  dev   = get_interface_guid(dev)
  addrs = NetworkInterface.addresses(dev)
  raise RuntimeError, "Interface #{dev} does not exist" if !addrs
  raise RuntimeError, "Interface #{dev} does not have an ipv4 address at position #{num}" if addrs[NetworkInterface::AF_INET].length < num + 1
  raise RuntimeError, "Cannot get the IPv4 address for interface #{dev}" if !addrs[NetworkInterface::AF_INET][num]['addr']
  addrs[NetworkInterface::AF_INET][num]['addr']
end

#get_ipv4_addr_count(dev) ⇒ Object

Raises:

  • (RuntimeError)


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# File 'lib/msf/core/exploit/capture.rb', line 487

def get_ipv4_addr_count(dev)
  check_pcaprub_loaded
  dev   = get_interface_guid(dev)
  addrs = NetworkInterface.addresses(dev)
  raise RuntimeError, "Interface #{dev} does not exist" if !addrs
  addrs[NetworkInterface::AF_INET].length
end

#get_ipv4_broadcast(dev, num = 0) ⇒ Object

Raises:

  • (RuntimeError)


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# File 'lib/msf/core/exploit/capture.rb', line 515

def get_ipv4_broadcast(dev, num=0)
  check_pcaprub_loaded
  dev   = get_interface_guid(dev)
  addrs = NetworkInterface.addresses(dev)
  raise RuntimeError, "Interface #{dev} do not exists" if !addrs
  raise RuntimeError, "Interface #{dev} do not have an ipv4 address at position #{num}" if addrs[NetworkInterface::AF_INET].length < num + 1
  raise RuntimeError, "Cannot get IPv4 broadcast address for interface #{dev}" if !addrs[NetworkInterface::AF_INET][num]['broadcast']
  addrs[NetworkInterface::AF_INET][num]['broadcast']
end

#get_ipv4_netmask(dev, num = 0) ⇒ Object

Raises:

  • (RuntimeError)


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# File 'lib/msf/core/exploit/capture.rb', line 505

def get_ipv4_netmask(dev, num=0)
  check_pcaprub_loaded
  dev   = get_interface_guid(dev)
  addrs = NetworkInterface.addresses(dev)
  raise RuntimeError, "Interface #{dev} does not exist" if !addrs
  raise RuntimeError, "Interface #{dev} does not have an ipv4 address at position #{num}" if addrs[NetworkInterface::AF_INET].length < num + 1
  raise RuntimeError, "Cannot get IPv4 netmask for interface #{dev}" if !addrs[NetworkInterface::AF_INET][num]['netmask']
  addrs[NetworkInterface::AF_INET][num]['netmask']
end

#get_ipv6_addr(dev, num = 0) ⇒ Object

NOTE: IPv6 is not implemented on Windows

Raises:

  • (RuntimeError)


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# File 'lib/msf/core/exploit/capture.rb', line 535

def get_ipv6_addr(dev, num=0)
  check_pcaprub_loaded
  dev = get_interface_guid(dev)
  raise RuntimeError, "IPv6 information is not available on this platform" unless ::NetworkInterface.const_defined?(:AF_INET6)
  addrs = NetworkInterface.addresses(dev)
  raise RuntimeError, "Interface #{dev} do not exists" if !addrs
  raise RuntimeError, "Interface #{dev} do not have an ipv6 address at position #{num}" if addrs[NetworkInterface::AF_INET6].length < num + 1
  raise RuntimeError, "Cannot get ipv6 address for interface #{dev}" if !addrs[NetworkInterface::AF_INET6][num]['addr']
  addrs[NetworkInterface::AF_INET6][num]['addr'].gsub(/%(.)*$/, '')
end

#get_ipv6_addr_count(dev) ⇒ Object

Raises:

  • (RuntimeError)


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# File 'lib/msf/core/exploit/capture.rb', line 525

def get_ipv6_addr_count(dev)
  check_pcaprub_loaded
  dev = get_interface_guid(dev)
  raise RuntimeError, "IPv6 information is not available on this platform" unless ::NetworkInterface.const_defined?(:AF_INET6)
  addrs = NetworkInterface.addresses(dev)
  raise RuntimeError, "Interface #{dev} do not exists" if !addrs
  addrs[NetworkInterface::AF_INET6].length
end

#get_ipv6_netmask(dev, num = 0) ⇒ Object

Raises:

  • (RuntimeError)


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# File 'lib/msf/core/exploit/capture.rb', line 546

def get_ipv6_netmask(dev, num=0)
  check_pcaprub_loaded
  dev = get_interface_guid(dev)
  raise RuntimeError, "IPv6 information is not available on this platform" unless ::NetworkInterface.const_defined?(:AF_INET6)
  addrs = NetworkInterface.addresses(dev)
  raise RuntimeError, "Interface #{dev} do not exists" if !addrs
  raise RuntimeError, "Interface #{dev} do not have an ipv6 address at position #{num}" if addrs[NetworkInterface::AF_INET6].length < num + 1
  raise RuntimeError, "Cannot get ipv6 netmask address for interface #{dev}" if !addrs[NetworkInterface::AF_INET6][num]['netmask']
  addrs[NetworkInterface::AF_INET6][num]['netmask']
end

#get_mac(dev) ⇒ Object

Raises:

  • (RuntimeError)


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# File 'lib/msf/core/exploit/capture.rb', line 478

def get_mac(dev)
  check_pcaprub_loaded
  dev   = get_interface_guid(dev)
  addrs = NetworkInterface.addresses(dev)
  raise RuntimeError, "Interface #{dev} does not exist" if !addrs
  raise RuntimeError, "Cannot get mac address for interface #{dev}" if !addrs[NetworkInterface::AF_LINK][0]['addr']
  addrs[NetworkInterface::AF_LINK][0]['addr']
end

#initialize(info = {}) ⇒ Object

Initializes an instance of an exploit module that captures traffic



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# File 'lib/msf/core/exploit/capture.rb', line 23

def initialize(info = {})
  super

  register_options(
    [
      OptPath.new('PCAPFILE', [false, 'The name of the PCAP capture file to process']),
      OptString.new('INTERFACE', [false, 'The name of the interface']),
      OptString.new('FILTER', [false, 'The filter string for capturing traffic']),
      OptInt.new('SNAPLEN', [true, 'The number of bytes to capture', 65535]),
      OptInt.new('TIMEOUT', [true, 'The number of seconds to wait for new data', 500]),
      Opt::RHOST

    ], Msf::Exploit::Capture
  )

  register_advanced_options(
    [
      OptInt.new('SECRET', [true, 'A 32-bit cookie for probe requests.', 'MSF!'.unpack('N').first]),
      OptAddress.new('GATEWAY_PROBE_HOST',
                     [
                       true,
                       'Send a TTL=1 random UDP datagram to this host to discover the default gateway\'s MAC',
                       '8.8.8.8']),
      OptPort.new('GATEWAY_PROBE_PORT',
                  [
                    false,
                    'The port on GATEWAY_PROBE_HOST to send a random UDP probe to (random if 0 or unset)'])
    ], Msf::Exploit::Capture
  )

  require 'packetfu'

  begin
    require 'pcaprub'
    @pcaprub_loaded = true
  rescue ::LoadError => e
    @pcaprub_loaded = false
    @pcaprub_error  = e
  end

  begin
    require 'network_interface'
    @network_interface_loaded = true
  rescue ::LoadError => e
    @network_interface_loaded = false
    @network_interface_error  = e
  end

end

#inject(pkt = "", pcap = self.capture) ⇒ Object

Injects a packet on the wire. For all injection-related functions, it’s on the module to open up a capture device first (this way, we don’t needlessly spawn new capture devices).



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# File 'lib/msf/core/exploit/capture.rb', line 180

def inject(pkt="", pcap=self.capture)
  check_pcaprub_loaded
  if not pcap
    raise RuntimeError, "Could not access the capture process (remember to open_pcap first!)"
  else
    pcap.inject(pkt.to_s) # Can be a PacketFu Packet object or a pre-packed string
  end
end

#inject_eth(args = {}) ⇒ Object

Injects an Ethernet packet with an optional payload. The payload may be a regular PacketFu packet, an EthHeader, or a string.



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# File 'lib/msf/core/exploit/capture.rb', line 191

def inject_eth(args={})
  eth_daddr   = args[:eth_daddr] || "ff:ff:ff:ff:ff:ff"
  eth_saddr   = args[:eth_saddr] || "00:00:00:00:00:00"
  eth_type    = args[:eth_type] || 0x0800 # IP default
  payload     = args[:payload]
  pcap        = args[:pcap] || self.capture
  p           = PacketFu::EthPacket.new
  p.eth_daddr = eth_daddr
  p.eth_saddr = eth_saddr
  p.eth_proto = eth_type
  if payload
    if payload.kind_of? PacketFu::EthPacket
      p.payload = payload.eth_header.body
    elsif payload.kind_of? PacketFu::EthHeader
      p.payload = payload.body
    else
      p.payload = payload.to_s
    end
  end
  inject p.to_s, pcap
end

#inject_pcap(pcap_file, filter = nil, delay = 0, pcap = self.capture) ⇒ Object



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# File 'lib/msf/core/exploit/capture.rb', line 213

def inject_pcap(pcap_file, filter=nil, delay = 0, pcap=self.capture)
  check_pcaprub_loaded
  unless pcap
    raise RuntimeError, "Could not access the capture process (remember to open_pcap first!)"
  end

  if (not File.exist?(pcap_file))
    raise RuntimeError, "The PCAP file #{pcap_file} could not be found"
  end

  if (pcap_file.empty?)
    raise RuntimeError, "The PCAP file #{pcap_file} is empty"
  end

  capture_file = ::Pcap.open_offline(pcap_file)
  capture_file.setfilter(filter) if filter
  while (pkt = capture_file.next) do
    pcap.inject(pkt)
    Rex.sleep((delay * 1.0)/1000)
  end
end

#inject_reply(proto = :udp, pcap = self.capture) ⇒ Object

The return value either be a PacketFu::Packet object, or nil

Raises:

  • (RuntimeError)


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# File 'lib/msf/core/exploit/capture.rb', line 258

def inject_reply(proto=:udp, pcap=self.capture)
  # Defaults to ~2 seconds
  to = ((datastore['TIMEOUT'] || 500).to_f * 4) / 1000.0
  raise RuntimeError, "Could not access the capture process (remember to open_pcap first!)" if not pcap
  begin
    ::Timeout.timeout(to) do
      pcap.each do |r|
        packet = PacketFu::Packet.parse(r)
        next unless packet.proto.map { |x| x.downcase.to_sym }.include? proto
        return packet
      end
    end
  rescue ::Timeout::Error
  end
 nil
end

#is_interface?(dev) ⇒ Boolean

Returns:

  • (Boolean)


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# File 'lib/msf/core/exploit/capture.rb', line 441

def is_interface?(dev)
  check_pcaprub_loaded
  if RUBY_PLATFORM == "i386-mingw32"
    if dev =~ /\\Device\\NPF_\{[A-F0-9]{8}-[A-F0-9]{4}-[A-F0-9]{4}-[A-F0-9]{4}-[A-F0-9]{12}\}/
      return NetworkInterface.interfaces.include?(dev)
    elsif dev.to_s =~ /^[0-9]{1,2}$/
      if (dev.to_i <= NetworkInterface.interfaces.length) and (dev.to_i >= 0)
        return true
      else
        return false
      end
    else
      return false
    end
  else
    return NetworkInterface.interfaces.include?(dev)
  end
end

#list_interfacesObject



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# File 'lib/msf/core/exploit/capture.rb', line 436

def list_interfaces
  check_pcaprub_loaded
  NetworkInterface.interfaces
end

#lookup_eth(addr = nil, iface = nil) ⇒ Object

This ascertains the correct Ethernet addresses one should use to ensure injected IP packets actually get where they are going, and manages the self.arp_cache hash. It always uses self.arp_capture to inject and capture packets, and will always first fire off a UDP packet using the regular socket to learn the source host’s and gateway’s mac addresses.

Raises:

  • (RuntimeError)


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# File 'lib/msf/core/exploit/capture.rb', line 281

def lookup_eth(addr=nil, iface=nil)
  raise RuntimeError, "Could not access the capture process." unless self.arp_capture

  self.arp_cache ||= {}
  self.dst_cache ||= {}

  return self.dst_cache[addr] if self.dst_cache[addr]

  if !self.arp_cache[Rex::Socket.source_address(addr)]
    probe_gateway(addr)
  end

  src_mac = self.arp_cache[Rex::Socket.source_address(addr)]
  if should_arp?(addr)
    dst_mac = self.arp_cache[addr] || arp(addr)
  else
    dst_mac = self.arp_cache[:gateway]
  end

  self.dst_cache[addr] = [dst_mac, src_mac]
end

#lookupnetObject



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# File 'lib/msf/core/exploit/capture.rb', line 406

def lookupnet
  check_pcaprub_loaded
  dev  = datastore['INTERFACE'] || ::Pcap.lookupdev
  begin
    my_ip, my_mask = Pcap.lookupnet(dev)
    # convert the netmask obtained from the relevant interface to CIDR
    cidr_mask = my_mask.to_s(2).count('1')
    my_net = IPAddr.new("#{my_ip}/#{cidr_mask}")
  rescue RuntimeError => e
    @pcaprub_error = e
    print_status("Cannot stat device: #{@pcaprub_error}")
    raise RuntimeError, "Pcaprub error: #{@pcaprub_error}"
  end
  return my_net
end

#netifaces_implemented?Boolean

Netifaces code

Returns:

  • (Boolean)


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# File 'lib/msf/core/exploit/capture.rb', line 430

def netifaces_implemented?
  @network_interface_loaded and
    NetworkInterface.respond_to?(:interfaces) and
    NetworkInterface.respond_to?(:addresses)
end

#open_pcap(opts = {}) ⇒ Object

Opens a handle to the specified device



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# File 'lib/msf/core/exploit/capture.rb', line 91

def open_pcap(opts={})
  check_pcaprub_loaded
  if RUBY_PLATFORM == "i386-mingw32"
    if opts['INTERFACE'] or datastore['INTERFACE']
      dev = opts['INTERFACE'] || datastore['INTERFACE']
      if is_interface?(dev)
        dev = get_interface_guid(dev)
      end
    end
  else
    dev = opts['INTERFACE'] || datastore['INTERFACE'] || nil
  end

  len = (opts['SNAPLEN'] || datastore['SNAPLEN'] || 65535).to_i
  tim = (opts['TIMEOUT'] || datastore['TIMEOUT'] || 0).to_i
  fil = opts['FILTER'] || datastore['FILTER']
  do_arp = (opts['ARPCAP'] == false) ? false : true

  # Look for a PCAP file
  cap = datastore['PCAPFILE'] || ''

  if (not cap.empty?)
    if (not File.exist?(cap))
      raise RuntimeError, "The PCAP file #{cap} could not be found"
    end
    self.capture = ::Pcap.open_offline(cap)
  else
    dev ||= ::Pcap.lookupdev

    unless RUBY_PLATFORM == "i386-mingw32"
      system("ifconfig", dev, "up")
    end

    self.capture = ::Pcap.open_live(dev, len, true, tim)
    if do_arp
      self.arp_capture = ::Pcap.open_live(dev, 512, true, tim)
      preamble         = datastore['SECRET'].to_i
      arp_filter       = "arp[6:2] = 2 or (udp[8:4] = #{preamble})"
      self.arp_capture.setfilter(arp_filter)
    end
  end

  if (not self.capture)
    raise RuntimeError, "Could not start the capture process"
  elsif (do_arp and !self.arp_capture and cap.empty?)
    raise RuntimeError, "Could not start the ARP capture process"
  end

  self.capture.setfilter(fil) if fil
end

#probe_gateway(addr) ⇒ Object



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# File 'lib/msf/core/exploit/capture.rb', line 303

def probe_gateway(addr)
  dst_host = datastore['GATEWAY_PROBE_HOST']
  dst_port = datastore['GATEWAY_PROBE_PORT'].to_i == 0 ? rand(30000) + 1024 : datastore['GATEWAY_PROBE_PORT']
  preamble = [datastore['SECRET']].pack("N")
  secret   = "#{preamble}#{Rex::Text.rand_text(rand(0xff)+1)}"

  begin
    UDPSocket.open do |sock|
      sock.setsockopt(::Socket::IPPROTO_IP, ::Socket::IP_TTL, 1)
      sock.send(secret, 0, dst_host, dst_port)
    end
  rescue Errno::ENETUNREACH
    # This happens on networks with no gateway. We'll need to use a
    # fake source hardware address.
    self.arp_cache[Rex::Socket.source_address(addr)] = "00:00:00:00:00:00"
  end

  begin
    to = ((datastore['TIMEOUT'] || 500).to_f * 8) / 1000.0
    ::Timeout.timeout(to) do
      loop do
        my_packet = inject_reply(:udp, self.arp_capture)
        next unless my_packet
        next unless my_packet.payload == secret
        dst_mac = self.arp_cache[:gateway] = my_packet.eth_daddr
        src_mac = self.arp_cache[Rex::Socket.source_address(addr)] = my_packet.eth_saddr
        return [dst_mac, src_mac]
      end
    end
  rescue ::Timeout::Error
    # Well, that didn't work (this is common on networks where there's no gateway, like
    # VMWare network interfaces. We'll need to use a fake source hardware address.
    self.arp_cache[Rex::Socket.source_address(addr)] = "00:00:00:00:00:00"
  end
end

#rhostObject

For compatibility with Msf::Exploit::Remote::Ip



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# File 'lib/msf/core/exploit/capture.rb', line 390

def rhost
  datastore['RHOST']
end

#should_arp?(ip) ⇒ Boolean

Returns:

  • (Boolean)


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# File 'lib/msf/core/exploit/capture.rb', line 422

def should_arp?(ip)
  lookupnet.include?(IPAddr.new(ip))
end

#stats_drop(pcap = self.capture) ⇒ Object



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# File 'lib/msf/core/exploit/capture.rb', line 78

def stats_drop(pcap=self.capture)
  return(0) unless pcap
  pcap.stats['drop']
end

#stats_ifdrop(pcap = self.capture) ⇒ Object



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# File 'lib/msf/core/exploit/capture.rb', line 83

def stats_ifdrop(pcap=self.capture)
  return(0) unless pcap
  pcap.stats['ifdrop']
end

#stats_recv(pcap = self.capture) ⇒ Object



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# File 'lib/msf/core/exploit/capture.rb', line 73

def stats_recv(pcap=self.capture)
  return(0) unless pcap
  pcap.stats['recv']
end