This version implements the support for Multipath TCP.

It affects the way TCP is handled by adding a packet type for TCP options.  It
also adds a packet type MPTCP as subtype of a TCP option (see
scapy/layers/mptcp.py for details).

You can use the script "launcher" to start scapy with the modified script. It
works only if you are in the same directory that the python "scapy" module.

EXAMPLE RUN
===========

$ ./laucher
Welcome to Scapy (2.2.0)
>>> a=rdpcap("dumps/mptcp-capable.pcap")
>>> a
<mptcp-capable.pcap: TCP:1 UDP:0 ICMP:0 Other:0>
>>> a[0]
<CookedLinux  pkttype=sent-by-us lladdrtype=0x1 lladdrlen=6 src='\x00%\xb3\x02\xd24' proto=0x800 |<IP  version=4L ihl=5L tos=0x0 len=80 id=32501 flags=DF frag=0L ttl=64 proto=tcp chksum=0xa5a7 src=10.0.1.11 dst=10.0.1.1 options=[] |<TCP  sport=44437 dport=www seq=559395504 ack=169850675 dataofs=15L reserved=0L flags=A window=28 chksum=0x164e urgptr=0 options=[<TCPOption_NOP  kind=NOP |>, <TCPOption_NOP  kind=NOP |>, <TCPOption_Timestamp  kind=Timestamp length=10 timestamp_value=183387 timestamp_echo=178863 |>, <TCPOption_MP  kind=MpTCP mptcp=<MPTCP_Capable  length=20 subtype=MP_CAPABLE version=0L checksum_req=1L reserved=0L hmac_sha1=1L snd_key=1815828401224581229 rcv_key=8653733315196113643 |> |>, <TCPOption_MP  kind=MpTCP mptcp=<MPTCP_AddAddr  length=8 subtype=ADD_ADDR ipver=4L address_id=1 adv_addr=10.0.0.7 |> |>] |>>>
>> a[0].show2()
###[ cooked linux ]###
  pkttype= sent-by-us
  lladdrtype= 0x1
  lladdrlen= 6
  src= '\x00%\xb3\x02\xd24'
  proto= 0x800
###[ IP ]###
     version= 4L
     ihl= 5L
     tos= 0x0
     len= 80
     id= 32501
     flags= DF
     frag= 0L
     ttl= 64
     proto= tcp
     chksum= 0xa5a7
     src= 10.0.1.11
     dst= 10.0.1.1
     \options\
###[ TCP ]###
        sport= 44437
        dport= www
        seq= 559395504
        ack= 169850675
        dataofs= 15L
        reserved= 0L
        flags= A
        window= 28
        chksum= 0x164e
        urgptr= 0
        \options\
         |###[ No Operation ]###
         |  kind= NOP
         |###[ No Operation ]###
         |  kind= NOP
         |###[ Timestamp ]###
         |  kind= Timestamp
         |  length= 10
         |  timestamp_value= 183387
         |  timestamp_echo= 178863
         |###[ Multipath TCP option ]###
         |  kind= MpTCP
         |  \mptcp\
         |   |###[ Multipath TCP capability ]###
         |   |  length= 20
         |   |  subtype= MP_CAPABLE
         |   |  version= 0L
         |   |  checksum_req= 1L
         |   |  reserved= 0L
         |   |  hmac_sha1= 1L
         |   |  snd_key= 1815828401224581229
         |   |  rcv_key= 8653733315196113643
         |###[ Multipath TCP option ]###
         |  kind= MpTCP
         |  \mptcp\
         |   |###[ Multipath TCP Add Address ]###
         |   |  length= 8
         |   |  subtype= ADD_ADDR
         |   |  ipver= 4L
         |   |  address_id= 1
         |   |  adv_addr= 10.0.0.7