[ovs-dev] Mask generation for megaflow.

[Subrata Paul]

Hi,
I am using ovs 2.4.0 and I have added 3 flows as follows:
ovs-ofctl add-flow br0 "table=0, in_port=1, tcp, nw_src=10.0.0.2/24, tcp_src=45466, action=output:2"
ovs-ofctl add-flow br0 "table=0, in_port=1, tcp, nw_dst=10.0.0.2/24, tcp_dst=442, action=output:2"
ovs-ofctl add-flow br0 "table=0, in_port=1, tcp, nw_dst=10.0.0.2/24, tcp_dst=450, action=output:2"

Then I sent 3 packets to ovs with:

1.  Src port: 45466, dst_port:436

2.  Src port: 45328, dst_port:450

3.  Src port: 45468, dst_port:442


The megaflows installed in datapath are:
      recirc_id(0),in_port(1),eth_type(0x0800),ipv4(src=10.0.0.2/255.255.255.0,proto=6,frag=no),tcp(src=45466), packets:0, bytes:0, used:never, actions:2
recirc_id(0),in_port(1),eth_type(0x0800),ipv4(src=10.0.0.5/255.255.255.0,dst=10.0.0.2/255.255.255.0,proto=6,frag=no),tcp(src=45328/0x2,dst=450), packets:0, bytes:0, used:never, actions:2
recirc_id(0),in_port(1),eth_type(0x0800),ipv4(src=10.0.0.5/255.255.255.0,dst=10.0.0.2/255.255.255.0,proto=6,frag=no),tcp(src=45468/0x2,dst=442), packets:0, bytes:0, used:never, actions:2

My doubt is how src=45328/0x2 got generated from the flows. Basically the mask 0x2. Please help me understanding the mask generation from the flows added for the megaflow.


Thanks and regards,
Subrata Paul