Add support for vdev tap devices

This commit adds support for the creation of tap devices.
To create a tap device, and associate it with a DPDK port,
add within the port section:
vdev=<tap_name>
local ipv4=<ip_assigned_to_port>
<tap_name> will appear as a kernel network device, with an IP <ip_assigned_to_port>

ARP packets received from the network on the DPDK interface will be forwarded to the kernel.
1st packet which needs to be generated to a new IP will cause an IP packet
to be sent to the kernel (using socket sendto) forcing the kernel to send an ARP_REQUEST.

In this commit, there is no notification from the kernel about ARP table changes.
This is subject to further commits.

Two config files, gen_tap.cfg and swap_tap.cfg have been created. They work one against each other.
*** Note however that they do not work if running within the same host
(with the port being connected back to back) ***
This is due to the fact that the kernel would bypass the ports and use local interface...

Change-Id: Iadeec0d99e3c693472ea44bdb9163a3bf97df2fa
Signed-off-by: Xavier Simonart <xavier.simonart@intel.com>

1 files changed, 50 insertions, 0 deletions

diff --git a/VNFs/DPPD-PROX/swap_tap.cfg b/VNFs/DPPD-PROX/swap_tap.cfg
new file mode 100644
index 00000000..5777f9d9
--- /dev/null
+++ b/VNFs/DPPD-PROX/swap_tap.cfg
@@ -0,0 +1,50 @@
+;;
+;; Copyright (c) 2020 Intel Corporation
+;;
+;; Licensed under the Apache License, Version 2.0 (the "License");
+;; you may not use this file except in compliance with the License.
+;; You may obtain a copy of the License at
+;;
+;;     http://www.apache.org/licenses/LICENSE-2.0
+;;
+;; Unless required by applicable law or agreed to in writing, software
+;; distributed under the License is distributed on an "AS IS" BASIS,
+;; WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+;; See the License for the specific language governing permissions and
+;; limitations under the License.
+;;
+
+[eal options]
+-n=4 ; force number of memory channels
+no-output=no ; disable DPDK debug output
+
+[port 0]
+name=p0
+vdev=swap_tap
+local ipv4=$ip2
+
+[defaults]
+mempool size=16K
+
+[global]
+start time=5
+name=Basic Gen
+
+[variables]
+$hex_ip1=0a 0a 0a 01
+$hex_ip2=0a 0a 0a 02
+$ip1=10.10.10.1
+$ip2=10.10.10.2
+
+[core 0s0]
+mode=master
+
+[core 1s0]
+name=swap
+task=0
+mode=swap
+sub mode=l3
+rx port=p0
+tx port=p0
+drop=no
+local ipv4=${ip2}