On Wed, Mar 29, 2017 at 11:12 PM, Ben Pfaff <b...@ovn.org> wrote: > On Mon, Mar 27, 2017 at 07:42:58PM +0530, nusid...@redhat.com wrote: > > From: Numan Siddique <nusid...@redhat.com> > > > > This patch adds a new OVN action 'dns_lookup' to support native DNS. > > ovn-controller parses this action and adds a NXT_PACKET_IN2 > > OF flow with 'pause' flag set. > > > > A new table 'DNS' is added in the SB DB to look up and resolve > > the DNS queries. When a valid DNS packet is received by > > ovn-controller, it looks up the DNS name in the 'DNS' table > > and if successful, it frames a DNS reply, resumes the packet > > and stores 1 in the 1-bit subfield. If the packet is invalid > > or cannot be resolved, it resumes the packet without any > > modifications and stores 0 in the 1-bit subfield. > > > > reg0[4] = dns_lookup(); next; > > > > An upcoming patch will use this action and adds logical flows. > > > > Signed-off-by: Numan Siddique <nusid...@redhat.com> > > I didn't do a thorough review, but here's a suggested incremental for > the documentation. (I started by noticing that a DNS request should > have udp.dst 53, not udp.src 53, and then got carried away a little.) > > Thanks Ben for pointing out and correcting it. Before I update the patch, I would like to know your opinion on the approach suggested by Guru - ( https://mail.openvswitch.org/pipermail/ovs-dev/2017-March/330235.html) as that may require some changes in this patch as well.
Thanks Numan diff --git a/ovn/ovn-sb.xml b/ovn/ovn-sb.xml > index e0e4f67b3bb6..692925aa9856 100644 > --- a/ovn/ovn-sb.xml > +++ b/ovn/ovn-sb.xml > @@ -1482,21 +1482,21 @@ > </p> > > <p> > - When this action is applied to a valid DNS (UDP packet with > - udp.src 53) request packet, it changes the packet into a DNS > reply > - if it is able to resolve the query and stores 1 in > <var>R</var>. > - It leaves the packet unchanged if it is not able to resolve > and > - stores 0 in <var>R</var>. > + When this action is applied to a valid DNS request (a UDP > packet > + typically directed to port 53), it attempts to resolve the > query > + using the contents of the <ref table="DNS"/> table. If it is > + successful, it changes the packet into a DNS reply and stores > 1 in > + <var>R</var>. If the action is applied to a non-DNS packet, > an > + invalid DNS request packet, or a valid DNS request for which > the > + <ref table="DNS"/> table does not supply an answer, it leaves > the > + packet unchanged and stores 0 in <var>R</var>. > </p> > > <p> > - When this action is applied to a non-DNS or an invalid > - DNS request packet , it leaves the packet unchanged and stores > - 0 in <var>R</var>. > - </p> > - > - <p> > - The contents of the <ref table="DNS"/> table control the DNS > lookup. > + Regardless of success, the action does not make any of the > changes > + to the flow that are necessary to direct the packet back to > the > + requester. The logical pipeline can implement this behavior > with > + matches and actions in later tables. > </p> > > <p> > @@ -1505,6 +1505,10 @@ > reg0[3] = dns_lookup(); > </code> > </p> > + > + <p> > + <b>Prerequisite:</b> <code>udp</code> > + </p> > </dd> > </dl> > > _______________________________________________ dev mailing list d...@openvswitch.org https://mail.openvswitch.org/mailman/listinfo/ovs-dev
