Simple question, what do you do for packet without UDP/TCP port?  Like
ICMP, ARP, etc?  That logic seems missing.

Regards
KK

On 28 November 2010 16:22, K Singh <kavites...@gmail.com> wrote:
> Hi,
>
> I modified the code below for function def forward_l2_packet(...) in
> pyswitch.py.
>
> def forward_l2_packet(dpid, inport, packet, buf, bufid):
>
>     dstaddr = packet.dst.tostring()
>     if not ord(dstaddr[0]) & 1 and inst.st[dpid].has_key(dstaddr):
>         prt = inst.st[dpid][dstaddr]
>         if  prt[0] == inport:
>             log.err('**warning** learned port = inport', system="pyswitch")
>             inst.send_openflow(dpid, bufid, buf, openflow.OFPP_FLOOD,
> inport)
>         else:
>             # We know the outport, set up a flow
>             log.msg('installing flow for ' + str(packet), system="pyswitch")
>             flow = extract_flow(packet)
>             flow[core.IN_PORT] = inport
>             actions = [[openflow.OFPAT_OUTPUT, [0, prt[0]]]]
>             # openflow.OFP_FLOW_PERMANENT
>             renewflag = flowpacketdecision(dpid, flow, packet, inport, buf)
>             print "renewflag",renewflag
>             #print packet
>             if renewflag == 1:
>                 inst.install_datapath_flow(dpid, flow, CACHE_TIMEOUT,5,
> actions,bufid, openflow.OFP_DEFAULT_PRIORITY,inport, buf)
>
>     else:
>         # haven't learned destination MAC. Flood
>         inst.send_openflow(dpid, bufid, buf, openflow.OFPP_FLOOD, inport)
>
>
> The red highlighted part is where i made changes. I am making decision on
> setting flow based on port numbers whose logic is in
> flowpacketdecision(...). If the function returns 1 i renew or set the flow
> else i reject the packet and wait for another packet to come.
>
> But this logic, fails for ARP packet. Because in my flowpacketdecision(..) i
> am checking for TCP/UDP packet and renewing/setting the flow. If i receive
> ARP packet then in the current code it is not renewing/setting the flow.
> This means i cant proceed with TCP/UDP code anyways connection timeout when
> tested in iperf.
>
> If i check for ARP packets and set the reneweflag = 1 then anyways the flow
> is getting set irrespective of my logic. I even tried commenting the
> timer_callback function which removes the MAC entries so that ARP message
> are not sent again after initially learning about MAC addresses. It didnt
> work. Is there anyway I can block the ARP messages once transmitted and then
> only have TCP/UDP messages flowing in the network.
>
> --
> Regards,
> Kavitesh Singh.
>
>
> _______________________________________________
> nox-dev mailing list
> nox-dev@noxrepo.org
> http://noxrepo.org/mailman/listinfo/nox-dev_noxrepo.org
>
>

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