Hi All,

I tried to modify the packet header (destination ip and mac) and forward
the

packet to the new destination (modified packet header about destination ip
and

mac).

The code is below. I can't do what i want.

what should i do ?

   def add_flow(self, datapath, priority, match, actions, buffer_id=None):
        ofproto = datapath.ofproto
        parser = datapath.ofproto_parser

        inst = [parser.OFPInstructionActions(ofproto.OFPIT_APPLY_ACTIONS,
                                             actions)]
        if buffer_id:
            mod = parser.OFPFlowMod(datapath=datapath, buffer_id=buffer_id,
                                    priority=priority, match=match,
                                    instructions=inst)
        else:
            mod = parser.OFPFlowMod(datapath=datapath, priority=priority,
                                    match=match, instructions=inst)
        datapath.send_msg(mod)

    @set_ev_cls(ofp_event.EventOFPPacketIn, MAIN_DISPATCHER)
    def _packet_in_handler(self, ev):
        if ev.msg.msg_len < ev.msg.total_len:
            self.logger.debug("packet truncated: only %s of %s bytes",
                              ev.msg.msg_len, ev.msg.total_len)
        msg = ev.msg
        datapath = msg.datapath
        ofproto = datapath.ofproto
        parser = datapath.ofproto_parser
        in_port = msg.match['in_port']

        pkt = packet.Packet(msg.data)
        eth = pkt.get_protocols(ethernet.ethernet)[0]
        ip4_pkt = pkt.get_protocol(ipv4.ipv4)

        if eth.ethertype == ether_types.ETH_TYPE_LLDP:
            # ignore lldp packet
            return
        dst = eth.dst
        src = eth.src


        dpid = datapath.id
        self.mac_to_port.setdefault(dpid, {})

        self.logger.info("packet in %s %s %s %s", dpid, src, dst, in_port)

        # learn a mac address to avoid FLOOD next time.
        self.mac_to_port[dpid][src] = in_port

        if eth.ethertype == ether_types.ETH_TYPE_ARP:
            print("Yes, ARP Packet!!")

        else:
            print("NO!!")
            print(ip4_pkt.dst)
            print(ip4_pkt.src)

            #modify packet header
            actions_modify_headers =
[parser.OFPActionSetField(eth_dst="00:00:00:00:00:03"),
parser.OFPActionSetField

(ipv4_dst="10.1.1.2"),parser.OFPActionOutput(2)]
            match1 = parser.OFPMatch(in_port=3, eth_dst="00:00:00:00:00:01")

            self.add_flow(datapath, 1, match1, actions_modify_headers)

            out = parser.OFPPacketOut(datapath=datapath,
buffer_id=msg.buffer_id,
                                  in_port=in_port, actions=actions,
data=data)
            datapath.send_msg(out)



        if dst in self.mac_to_port[dpid]:
            out_port = self.mac_to_port[dpid][dst]


        else:
            out_port = ofproto.OFPP_FLOOD

        actions = [parser.OFPActionOutput(out_port)]

        # install a flow to avoid packet_in next time
        if out_port != ofproto.OFPP_FLOOD:
            match = parser.OFPMatch(in_port=in_port, eth_dst=dst)
            # verify if we have a valid buffer_id, if yes avoid to send both
            # flow_mod & packet_out
            if msg.buffer_id != ofproto.OFP_NO_BUFFER:
                self.add_flow(datapath, 1, match, actions, msg.buffer_id)
                return
            else:
                self.add_flow(datapath, 1, match, actions)
        data = None
        if msg.buffer_id == ofproto.OFP_NO_BUFFER:
            data = msg.data

        out = parser.OFPPacketOut(datapath=datapath,
buffer_id=msg.buffer_id,
                                  in_port=in_port, actions=actions,
data=data)
        datapath.send_msg(out)

Thanks,

Alan
------------------------------------------------------------------------------
Check out the vibrant tech community on one of the world's most 
engaging tech sites, SlashDot.org! http://sdm.link/slashdot
_______________________________________________
Ryu-devel mailing list
[email protected]
https://lists.sourceforge.net/lists/listinfo/ryu-devel

Reply via email to