OFPAT_SET_NW_DST should update the IP checksum. Are you sure that a bad checksum is the problem?
Remember that if you rewrite the DST when sending from A to B, you'll also need to rewrite the SRC when sending from B back to A. Host A doesn't know that you've rewritten the address and will have no idea that a message from some arbitrary address is supposed to be from B! As a sidenote, you seem to be reading from the OpenFlow 1.1 spec, but NOX currently only supports OpenFlow 1.0. -- Murphy On Jan 9, 2012, at 4:08 AM, Hyogi Jung wrote: > Hi, > > I want to change the destination address. > So I use these actions. And add output action. > > OFPAT_SET_DL_DST, /* Ethernet destination address. */ > OFPAT_SET_NW_DST, /* IP destination address. */ > > Finally destination node could receive the changed packet. > > But there is a problem. > I snoop the packets using wireshark. After 3-handshaking (SYN, SYN+ACK), the > sender node send "RST" packet. > I think it is occured by reason of "I didn't update the IP checksum." > > Openflow-spec describe below. > > Action : Set IPv4 destination address > Description : Replace the existing IP destination address with and update the > IP checksum (and TCP/UDP/SCTP checksum if applicable). > This action is only applied to IPv4 packets. > > But How can I update the IP checksum? > I use C/C++ languge. I try to find updating IP checksum problem in > nox-mailing list. > But I couldn't find it. > > Is it a possible using "send_openflow_command()" fuction or > "send_openflow_packet()" fuction? > > send_openflow_command() function = change original packet in switch using > flow action. > however, send_openflow_packet() = send new packet instructed by controller. > > Could you give some advice or reference source? > > Thank you. > > - Hyogi > _______________________________________________ > nox-dev mailing list > nox-dev@noxrepo.org > http://noxrepo.org/mailman/listinfo/nox-dev _______________________________________________ nox-dev mailing list nox-dev@noxrepo.org http://noxrepo.org/mailman/listinfo/nox-dev
