Ryu控制器编程开发——packet_in和packet_out简易交换机实现（二）

1、添加mac学习功能

2、给交换机下发流表

from ryu.base import app_manager
from ryu.controller import ofp_event
from ryu.controller.handler import MAIN_DISPATCHER
from ryu.controller.handler import set_ev_cls
from ryu.ofproto import ofproto_v1_0
from ryu.lib.mac import haddr_to_bin
from ryu.lib.packet import packet
from ryu.lib.packet import ethernet
from ryu.lib.packet import ether_types


class SimpleSwitch(app_manager.RyuApp):
    OFP_VERSIONS = [ofproto_v1_0.OFP_VERSION]

    def __init__(self, *args, **kwargs):
        super(SimpleSwitch, self).__init__(*args, **kwargs)
        self.mac_to_port = {}

    def add_flow(self, datapath, in_port, dst, src, actions):
        ofproto = datapath.ofproto

        match = datapath.ofproto_parser.OFPMatch(
            in_port=in_port,
            dl_dst=haddr_to_bin(dst), dl_src=haddr_to_bin(src))

        mod = datapath.ofproto_parser.OFPFlowMod(
            datapath=datapath, match=match, cookie=0,
            command=ofproto.OFPFC_ADD, idle_timeout=0, hard_timeout=0,
            priority=ofproto.OFP_DEFAULT_PRIORITY,
            flags=ofproto.OFPFF_SEND_FLOW_REM, actions=actions)
        datapath.send_msg(mod)

    @set_ev_cls(ofp_event.EventOFPPacketIn, MAIN_DISPATCHER)
    def _packet_in_handler(self, ev):
        msg = ev.msg
        datapath = msg.datapath
        ofproto = datapath.ofproto

        pkt = packet.Packet(msg.data)
        eth = pkt.get_protocol(ethernet.ethernet)

        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, msg.in_port)

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

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

        actions = [datapath.ofproto_parser.OFPActionOutput(out_port)]

        # install a flow to avoid packet_in next time
        if out_port != ofproto.OFPP_FLOOD:
            self.add_flow(datapath, msg.in_port, dst, src, actions)

        data = None
        if msg.buffer_id == ofproto.OFP_NO_BUFFER:
            data = msg.data

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

[root@kunpeng82 app]# ovs-ofctl dump-flows s1
 cookie=0x0, duration=10.967s, table=0, n_packets=4, n_bytes=280, in_port="s1-eth1",dl_src=da:54:a5:07:16:8d,dl_dst=2e:25:f2:98:49:13 actions=output:"s1-eth2"
 cookie=0x0, duration=9.967s, table=0, n_packets=4, n_bytes=280, in_port="s1-eth2",dl_src=2e:25:f2:98:49:13,dl_dst=da:54:a5:07:16:8d actions=output:"s1-eth1"
[root@kunpeng82 app]#

删除所有流表

[root@kunpeng82 app]# ovs-ofctl dump-flows s1
 cookie=0x0, duration=401.384s, table=0, n_packets=19, n_bytes=1638, in_port="s1-eth1",dl_src=da:54:a5:07:16:8d,dl_dst=2e:25:f2:98:49:13 actions=output:"s1-eth2"
 cookie=0x0, duration=400.384s, table=0, n_packets=19, n_bytes=1638, in_port="s1-eth2",dl_src=2e:25:f2:98:49:13,dl_dst=da:54:a5:07:16:8d actions=output:"s1-eth1"
[root@kunpeng82 app]# ovs-ofctl del-flows s1  in_port="s1-eth1"
[root@kunpeng82 app]# ovs-ofctl del-flows s1  in_port="s1-eth2"
[root@kunpeng82 app]# ovs-ofctl dump-flows s1
[root@kunpeng82 app]#

删除之后，h2 ping h1 ,mn会收到EventOFPPacketIn

EVENT ofp_event->SimpleSwitch EventOFPPacketIn
packet in 1 2e:25:f2:98:49:13 da:54:a5:07:16:8d 2
EVENT ofp_event->SimpleSwitch EventOFPPacketIn
packet in 1 da:54:a5:07:16:8d 2e:25:f2:98:49:13 1