Imported Upstream version 17.05

Change-Id: Id1e419c5a214e4a18739663b91f0f9a549f1fdc6
Signed-off-by: Christian Ehrhardt <christian.ehrhardt@canonical.com>

1 files changed, 197 insertions, 0 deletions

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+..  BSD LICENSE
+    Copyright(c) 2016 Intel Corporation. All rights reserved.
+    All rights reserved.
+
+    Redistribution and use in source and binary forms, with or without
+    modification, are permitted provided that the following conditions
+    are met:
+
+    * Redistributions of source code must retain the above copyright
+    notice, this list of conditions and the following disclaimer.
+    * Redistributions in binary form must reproduce the above copyright
+    notice, this list of conditions and the following disclaimer in
+    the documentation and/or other materials provided with the
+    distribution.
+    * Neither the name of Intel Corporation nor the names of its
+    contributors may be used to endorse or promote products derived
+    from this software without specific prior written permission.
+
+    THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+    "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+    LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+    A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+    OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+    SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+    LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+    DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+    THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+    (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+    OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+
+Tun/Tap Poll Mode Driver
+========================
+
+The ``rte_eth_tap.c`` PMD creates a device using TUN/TAP interfaces on the
+local host. The PMD allows for DPDK and the host to communicate using a raw
+device interface on the host and in the DPDK application.
+
+The device created is a TAP device, which sends/receives packet in a raw
+format with a L2 header. The usage for a TAP PMD is for connectivity to the
+local host using a TAP interface. When the TAP PMD is initialized it will
+create a number of tap devices in the host accessed via ``ifconfig -a`` or
+``ip`` command. The commands can be used to assign and query the virtual like
+device.
+
+These TAP interfaces can be used with Wireshark or tcpdump or Pktgen-DPDK
+along with being able to be used as a network connection to the DPDK
+application. The method enable one or more interfaces is to use the
+``--vdev=net_tap0`` option on the DPDK application command line. Each
+``--vdev=net_tap1`` option give will create an interface named dtap0, dtap1,
+and so on.
+
+The interface name can be changed by adding the ``iface=foo0``, for example::
+
+   --vdev=net_tap0,iface=foo0 --vdev=net_tap1,iface=foo1, ...
+
+Also the speed of the interface can be changed from 10G to whatever number
+needed, but the interface does not enforce that speed, for example::
+
+   --vdev=net_tap0,iface=foo0,speed=25000
+
+It is possible to specify a remote netdevice to capture packets from by adding
+``remote=foo1``, for example::
+
+   --vdev=net_tap,iface=tap0,remote=foo1
+
+If a ``remote`` is set, the tap MAC address will be set to match the remote one
+just after netdevice creation. Using TC rules, traffic from the remote netdevice
+will be redirected to the tap. If the tap is in promiscuous mode, then all
+packets will be redirected. In allmulti mode, all multicast packets will be
+redirected.
+
+Using the remote feature is especially useful for capturing traffic from a
+netdevice that has no support in the DPDK. It is possible to add explicit
+rte_flow rules on the tap PMD to capture specific traffic (see next section for
+examples).
+
+After the DPDK application is started you can send and receive packets on the
+interface using the standard rx_burst/tx_burst APIs in DPDK. From the host
+point of view you can use any host tool like tcpdump, Wireshark, ping, Pktgen
+and others to communicate with the DPDK application. The DPDK application may
+not understand network protocols like IPv4/6, UDP or TCP unless the
+application has been written to understand these protocols.
+
+If you need the interface as a real network interface meaning running and has
+a valid IP address then you can do this with the following commands::
+
+   sudo ip link set dtap0 up; sudo ip addr add 192.168.0.250/24 dev dtap0
+   sudo ip link set dtap1 up; sudo ip addr add 192.168.1.250/24 dev dtap1
+
+Please change the IP addresses as you see fit.
+
+If routing is enabled on the host you can also communicate with the DPDK App
+over the internet via a standard socket layer application as long as you
+account for the protocol handing in the application.
+
+If you have a Network Stack in your DPDK application or something like it you
+can utilize that stack to handle the network protocols. Plus you would be able
+to address the interface using an IP address assigned to the internal
+interface.
+
+Flow API support
+----------------
+
+The tap PMD supports major flow API pattern items and actions, when running on
+linux kernels above 4.2 ("Flower" classifier required). Supported items:
+
+- eth: src and dst (with variable masks), and eth_type (0xffff mask).
+- vlan: vid, pcp, tpid, but not eid. (requires kernel 4.9)
+- ipv4/6: src and dst (with variable masks), and ip_proto (0xffff mask).
+- udp/tcp: src and dst port (0xffff) mask.
+
+Supported actions:
+
+- DROP
+- QUEUE
+- PASSTHRU
+
+It is generally not possible to provide a "last" item. However, if the "last"
+item, once masked, is identical to the masked spec, then it is supported.
+
+Only IPv4/6 and MAC addresses can use a variable mask. All other items need a
+full mask (exact match).
+
+As rules are translated to TC, it is possible to show them with something like::
+
+   tc -s filter show dev tap1 parent 1:
+
+Examples of testpmd flow rules
+~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+
+Drop packets for destination IP 192.168.0.1::
+
+   testpmd> flow create 0 priority 1 ingress pattern eth / ipv4 dst is 1.1.1.1 \
+            / end actions drop / end
+
+Ensure packets from a given MAC address are received on a queue 2::
+
+   testpmd> flow create 0 priority 2 ingress pattern eth src is 06:05:04:03:02:01 \
+            / end actions queue index 2 / end
+
+Drop UDP packets in vlan 3::
+
+   testpmd> flow create 0 priority 3 ingress pattern eth / vlan vid is 3 / \
+            ipv4 proto is 17 / end actions drop / end
+
+Example
+-------
+
+The following is a simple example of using the TUN/TAP PMD with the Pktgen
+packet generator. It requires that the ``socat`` utility is installed on the
+test system.
+
+Build DPDK, then pull down Pktgen and build pktgen using the DPDK SDK/Target
+used to build the dpdk you pulled down.
+
+Run pktgen from the pktgen directory in a terminal with a commandline like the
+following::
+
+    sudo ./app/app/x86_64-native-linuxapp-gcc/app/pktgen -l 1-5 -n 4        \
+     --proc-type auto --log-level 8 --socket-mem 512,512 --file-prefix pg   \
+     --vdev=net_tap0 --vdev=net_tap1 -b 05:00.0 -b 05:00.1                  \
+     -b 04:00.0 -b 04:00.1 -b 04:00.2 -b 04:00.3                            \
+     -b 81:00.0 -b 81:00.1 -b 81:00.2 -b 81:00.3                            \
+     -b 82:00.0 -b 83:00.0 -- -T -P -m [2:3].0 -m [4:5].1                   \
+     -f themes/black-yellow.theme
+
+.. Note:
+
+   Change the ``-b`` options to blacklist all of your physical ports. The
+   following command line is all one line.
+
+   Also, ``-f themes/black-yellow.theme`` is optional if the default colors
+   work on your system configuration. See the Pktgen docs for more
+   information.
+
+Verify with ``ifconfig -a`` command in a different xterm window, should have a
+``dtap0`` and ``dtap1`` interfaces created.
+
+Next set the links for the two interfaces to up via the commands below::
+
+    sudo ip link set dtap0 up; sudo ip addr add 192.168.0.250/24 dev dtap0
+    sudo ip link set dtap1 up; sudo ip addr add 192.168.1.250/24 dev dtap1
+
+Then use socat to create a loopback for the two interfaces::
+
+    sudo socat interface:dtap0 interface:dtap1
+
+Then on the Pktgen command line interface you can start sending packets using
+the commands ``start 0`` and ``start 1`` or you can start both at the same
+time with ``start all``. The command ``str`` is an alias for ``start all`` and
+``stp`` is an alias for ``stop all``.
+
+While running you should see the 64 byte counters increasing to verify the
+traffic is being looped back. You can use ``set all size XXX`` to change the
+size of the packets after you stop the traffic. Use pktgen ``help``
+command to see a list of all commands. You can also use the ``-f`` option to
+load commands at startup in command line or Lua script in pktgen.