def on_established_outgoing(self, pkt, ip, tcp):
if FIN & tcp.flags:
self.end_fin(tcp)
self.state = STATES.FIN_WAIT_1
return _drop(pkt, ip)
if RST & tcp.flags:
self.state = STATES.CLOSED
# rst sequence?
return _drop(pkt, ip)
self.update_tcp(pkt, ip, tcp, True)
return _accept(pkt, ip)
def pkt_outgoing(self, pkt, ip, tcp):
if tcp.flags & RST:
self.state = STATES.CLOSED
return _drop(pkt, ip)
func = self.outgoing.get(self.state, self.pass_pkt_outgoing)
return func(self, pkt, ip, tcp)
def on_listen_incomming(self, pkt, ip, tcp):
if tcp.flags == ACK:
self.recover_syn(tcp)
if tcp.flags == SYN:
self.state = STATES.SYN_RECV
_accept(pkt, ip)
return _drop(pkt, ip)
def on_recover_incomming(self, pkt, ip, tcp):
if tcp.flags == ACK:
# because in some cases the syn ack wont register
# we skip the syn_sent state and assume the
# application got the SYN-ACK
self.recover_syn_ack_local(tcp)
self.state = STATES.SYN_SENT
return _drop(pkt, ip)
def on_fin_wait_1(self, pkt, ip, tcp):
# we dont distinguesh between fin_wait_1 and fin_wait_2
if tcp.flags & FIN:
self.state = STATES.CLOSED
return _accept(pkt, ip)
return _drop(pkt, ip)
def on_syn_sent_outgoing(self, pkt, ip, tcp):
if tcp.flags == ACK:
self.state = STATES.ESTABLISHED
return _drop(pkt, ip)
def on_syn_sent_incomming(self, pkt, ip, tcp):
if tcp.flags == SYN | ACK:
return _accept(pkt, ip)
return _drop(pkt, ip)
def on_closed_outgoing(self, pkt, ip, tcp):
if tcp.flags & SYN:
self.state = STATES.RECOVER
self.recover_seq_ack(pkt, ip, tcp)
return _accept(pkt, ip)
return _drop(pkt, ip)
def on_syn_rcv_outgoing(self, pkt, ip, tcp):
if ACK == tcp.flags:
self.state = STATES.ESTABLISHED
return _accept(pkt, ip)
return _drop(pkt, ip)
def on_syn_rcv_outgoing(self, pkt, ip, tcp):
if ACK | SYN == tcp.flags:
self.recover_ack(tcp)
return _drop(pkt, ip)