Fixes #222 : Hide MAC

lib/bettercap/context.rb

@@ -67,6 +67,7 @@ def initialize
     @firewall     = Firewalls::Base.get
     @memory       = Memory.new
     @iface        = nil
+    @original_mac = nil
     @gateway      = nil
     @targets      = []
     @spoofer      = nil
@@ -85,6 +86,17 @@ def update!
                             'correct network configuration, this could also happen if bettercap '\
                             'is launched from a virtual environment.' unless Network::Validator.is_ip?(gw)
 
+    unless @options.core.use_mac.nil?
+      cfg = PacketFu::Utils.ifconfig @options.core.iface
+      raise BetterCap::Error, "Could not determine IPv4 address of '#{@options.core.iface}', make sure this interface "\
+                              'is active and connected.' if cfg[:ip4_obj].nil?
+
+      @original_mac = Network::Target.normalized_mac(cfg[:eth_saddr])
+
+      Logger.info "Changing interface MAC address to #{@options.core.use_mac}"
+
+      Shell.ifconfig( "#{@options.core.iface} ether #{@options.core.use_mac}")
+    end
 
     cfg = PacketFu::Utils.ifconfig @options.core.iface
     raise BetterCap::Error, "Could not determine IPv4 address of '#{@options.core.iface}', make sure this interface "\
@@ -183,6 +195,8 @@ def finalize
 
     @dnsd.stop unless @dnsd.nil?
     @httpd.stop unless @httpd.nil?
+
+    Shell.ifconfig( "#{@options.core.iface} ether #{@original_mac}") unless @original_mac.nil?
   end
 
   private

lib/bettercap/options/core_options.rb

@@ -39,6 +39,8 @@ class CoreOptions
   attr_accessor :packet_throttle
   # If true, bettercap will check for updates then exit.
   attr_accessor :check_updates
+  # If not nil, the interface MAC address will be changed to this value.
+  attr_accessor :use_mac
 
   def initialize( iface )
     @iface           = iface
@@ -53,6 +55,7 @@ def initialize( iface )
     @no_target_nbns  = false
     @packet_throttle = 0.0
     @check_updates   = false
+    @use_mac         = nil
   end
 
   def parse!( ctx, opts )
@@ -64,6 +67,15 @@ def parse!( ctx, opts )
       @iface = v
     end
 
+    opts.on( '--use-mac ADDRESS', 'Change the interface MAC address to this value before performing the attack.' ) do |v|
+      @use_mac = v
+      raise BetterCap::Error, "Invalid MAC address specified." unless Network::Validator.is_mac?(@use_mac)
+    end
+
+    opts.on( '--random-mac', 'Change the interface MAC address to a random one before performing the attack.' ) do |v|
+      @use_mac = [format('%0.2x', rand(256) & ~1), (1..5).map { format('%0.2x', rand(256)) }].join(':')
+    end
+
     opts.on( '-G', '--gateway ADDRESS', 'Manually specify the gateway address, if not specified the current gateway will be retrieved and used. ' ) do |v|
       @gateway = v
       raise BetterCap::Error, "The specified gateway '#{v}' is not a valid IPv4 address." unless Network::Validator.is_ip?(v)