..  SPDX-License-Identifier: BSD-3-Clause
    Copyright 2017 Mellanox Technologies, Ltd

Generic flow API - examples
===========================

This document demonstrates some concrete examples for programming flow rules
with the ``rte_flow`` APIs.

* Detail of the rte_flow APIs can be found in the following link:
  :doc:`../prog_guide/ethdev/flow_offload`.

* Details of the TestPMD commands to set the flow rules can be found in the
  following link: :ref:`TestPMD Flow rules <testpmd_rte_flow>`

Simple IPv4 drop
----------------

Description
~~~~~~~~~~~

In this example we will create a simple rule that drops packets whose IPv4
destination equals 192.168.3.2. This code is equivalent to the following
testpmd command (wrapped for clarity)::

  testpmd> flow create 0 ingress pattern eth / vlan /
                    ipv4 dst is 192.168.3.2 / end actions drop / end

Code
~~~~

.. code-block:: c

  /* create the attribute structure */
  struct rte_flow_attr attr = { .ingress = 1 };
  struct rte_flow_item pattern[MAX_PATTERN_IN_FLOW];
  struct rte_flow_action actions[MAX_ACTIONS_IN_FLOW];
  struct rte_flow_item_eth eth;
  struct rte_flow_item_vlan vlan;
  struct rte_flow_item_ipv4 ipv4;
  struct rte_flow *flow;
  struct rte_flow_error error;

  /* setting the eth to pass all packets */
  pattern[0].type = RTE_FLOW_ITEM_TYPE_ETH;
  pattern[0].spec = &eth;

  /* set the vlan to pass all packets */
  pattern[1] = RTE_FLOW_ITEM_TYPE_VLAN;
  pattern[1].spec = &vlan;

  /* set the dst ipv4 packet to the required value */
  ipv4.hdr.dst_addr = htonl(0xc0a80302);
  pattern[2].type = RTE_FLOW_ITEM_TYPE_IPV4;
  pattern[2].spec = &ipv4;

  /* end the pattern array */
  pattern[3].type = RTE_FLOW_ITEM_TYPE_END;

  /* create the drop action */
  actions[0].type = RTE_FLOW_ACTION_TYPE_DROP;
  actions[1].type = RTE_FLOW_ACTION_TYPE_END;

  /* validate and create the flow rule */
  if (!rte_flow_validate(port_id, &attr, pattern, actions, &error))
      flow = rte_flow_create(port_id, &attr, pattern, actions, &error);

Output
~~~~~~

Terminal 1: running sample app with the flow rule disabled::

  ./filter-program disable
  [waiting for packets]

Terminal 2: running scapy::

  $scapy
  welcome to Scapy
  >> sendp(Ether()/Dot1Q()/IP(src='176.80.50.4', dst='192.168.3.1'), \
           iface='some interface', count=1)
  >> sendp(Ether()/Dot1Q()/IP(src='176.80.50.5', dst='192.168.3.2'), \
           iface='some interface', count=1)

Terminal 1: output log::

  received packet with src ip = 176.80.50.4
  received packet with src ip = 176.80.50.5

Terminal 1: running sample the app flow rule enabled::

  ./filter-program enabled
  [waiting for packets]

Terminal 2: running scapy::

  $scapy
  welcome to Scapy
  >> sendp(Ether()/Dot1Q()/IP(src='176.80.50.4', dst='192.168.3.1'),  \
           iface='some interface', count=1)
  >> sendp(Ether()/Dot1Q()/IP(src='176.80.50.5', dst ='192.168.3.2'), \
           iface='some interface', count=1)

Terminal 1: output log::

  received packet with src ip = 176.80.50.4

Range IPv4 drop
----------------

Description
~~~~~~~~~~~

In this example we will create a simple rule that drops packets whose IPv4
destination is in the range 192.168.3.0 to 192.168.3.255. This is done using
a mask.

This code is equivalent to the following testpmd command (wrapped for
clarity)::

  testpmd> flow create 0 ingress pattern eth / vlan /
                    ipv4 dst spec 192.168.3.0 dst mask 255.255.255.0 /
                    end actions drop / end

Code
~~~~

.. code-block:: c

  struct rte_flow_attr attr = {.ingress = 1};
  struct rte_flow_item pattern[MAX_PATTERN_IN_FLOW];
  struct rte_flow_action actions[MAX_ACTIONS_IN_FLOW];
  struct rte_flow_item_eth eth;
  struct rte_flow_item_vlan vlan;
  struct rte_flow_item_ipv4 ipv4;
  struct rte_flow_item_ipv4 ipv4_mask;
  struct rte_flow *flow;
  struct rte_flow_error error;

  /* setting the eth to pass all packets */
  pattern[0].type = RTE_FLOW_ITEM_TYPE_ETH;
  pattern[0].spec = &eth;

  /* set the vlan to pass all packets */
  pattern[1] = RTE_FLOW_ITEM_TYPE_VLAN;
  pattern[1].spec = &vlan;

  /* set the dst ipv4 packet to the required value */
  ipv4.hdr.dst_addr = htonl(0xc0a80300);
  ipv4_mask.hdr.dst_addr = htonl(0xffffff00);
  pattern[2].type = RTE_FLOW_ITEM_TYPE_IPV4;
  pattern[2].spec = &ipv4;
  pattern[2].mask = &ipv4_mask;

  /* end the pattern array */
  pattern[3].type = RTE_FLOW_ITEM_TYPE_END;

  /* create the drop action */
  actions[0].type = RTE_FLOW_ACTION_TYPE_DROP;
  actions[1].type = RTE_FLOW_ACTION_TYPE_END;

  /* validate and create the flow rule */
  if (!rte_flow_validate(port_id, &attr, pattern, actions, &error))
      flow = rte_flow_create(port_id, &attr, pattern, actions, &error);

Output
~~~~~~

Terminal 1: running sample app flow rule disabled::

  ./filter-program disable
  [waiting for packets]

Terminal 2: running scapy::

  $scapy
  welcome to Scapy
  >> sendp(Ether()/Dot1Q()/IP(src='176.80.50.4', dst='192.168.3.1'), \
           iface='some interface', count=1)
  >> sendp(Ether()/Dot1Q()/IP(src='176.80.50.5', dst='192.168.3.2'), \
           iface='some interface', count=1)
  >> sendp(Ether()/Dot1Q()/IP(src='176.80.50.6', dst='192.168.5.2'), \
           iface='some interface', count=1)

Terminal 1: output log::

  received packet with src ip = 176.80.50.4
  received packet with src ip = 176.80.50.5
  received packet with src ip = 176.80.50.6

Terminal 1: running sample app flow rule enabled::

  ./filter-program enabled
  [waiting for packets]

Terminal 2: running scapy::

  $scapy
  welcome to Scapy
  >> sendp(Ether()/Dot1Q()/IP(src='176.80.50.4', dst='192.168.3.1'), \
           iface='some interface', count=1)
  >> sendp(Ether()/Dot1Q()/IP(src='176.80.50.5', dst='192.168.3.2'), \
           iface='some interface', count=1)
  >> sendp(Ether()/Dot1Q()/IP(src='176.80.50.6', dst='192.168.5.2'), \
           iface='some interface', count=1)

Terminal 1: output log::

  received packet with src ip = 176.80.50.6

Send vlan to queue
------------------

Description
~~~~~~~~~~~

In this example we will create a rule that routes all vlan id 123 to queue 3.

This code is equivalent to the following testpmd command (wrapped for
clarity)::

  testpmd> flow create 0 ingress pattern eth / vlan vid spec 123 /
                    end actions queue index 3 / end

Code
~~~~

.. code-block:: c

  struct rte_flow_attr attr = { .ingress = 1 };
  struct rte_flow_item pattern[MAX_PATTERN_IN_FLOW];
  struct rte_flow_action actions[MAX_ACTIONS_IN_FLOW];
  struct rte_flow_item_eth eth;
  struct rte_flow_item_vlan vlan;
  struct rte_flow_action_queue queue = { .index = 3 };
  struct rte_flow *flow;
  struct rte_flow_error error;

  /* setting the eth to pass all packets */
  pattern[0].type = RTE_FLOW_ITEM_TYPE_ETH;
  pattern[0].spec = &eth;

  /* set the vlan to pas all packets */
  vlan.vid = 123;
  pattern[1] = RTE_FLOW_ITEM_TYPE_VLAN;
  pattern[1].spec = &vlan;

  /* end the pattern array */
  pattern[2].type = RTE_FLOW_ITEM_TYPE_END;

  /* create the queue action */
  actions[0].type = RTE_FLOW_ACTION_TYPE_QUEUE;
  actions[0].conf = &queue;
  actions[1].type = RTE_FLOW_ACTION_TYPE_END;

  /* validate and create the flow rule */
  if (!rte_flow_validate(port_id, &attr, pattern, actions, &error))
      flow = rte_flow_create(port_id, &attr, pattern, actions, &error);

Output
~~~~~~

Terminal 1: running sample app flow rule disabled::

  ./filter-program disable
  [waiting for packets]

Terminal 2: running scapy::

  $scapy
  welcome to Scapy
  >> sendp(Ether()/Dot1Q(vlan=123)/IP(src='176.80.50.4', dst='192.168.3.1'), \
           iface='some interface', count=1)
  >> sendp(Ether()/Dot1Q(vlan=50)/IP(src='176.80.50.5', dst='192.168.3.2'),  \
           iface='some interface', count=1)
  >> sendp(Ether()/Dot1Q(vlan=123)/IP(src='176.80.50.6', dst='192.168.5.2'), \
           iface='some interface', count=1)

Terminal 1: output log::

  received packet with src ip = 176.80.50.4 sent to queue 2
  received packet with src ip = 176.80.50.5 sent to queue 1
  received packet with src ip = 176.80.50.6 sent to queue 0

Terminal 1: running sample app flow rule enabled::

  ./filter-program enabled
  [waiting for packets]

Terminal 2: running scapy::

  $scapy
  welcome to Scapy
  >> sendp(Ether()/Dot1Q(vlan=123)/IP(src='176.80.50.4', dst='192.168.3.1'), \
           iface='some interface', count=1)
  >> sendp(Ether()/Dot1Q(vlan=50)/IP(src='176.80.50.5', dst='192.168.3.2'),  \
           iface='some interface', count=1)
  >> sendp(Ether()/Dot1Q(vlan=123)/IP(src='176.80.50.6', dst='192.168.5.2'), \
           iface='some interface', count=1)

Terminal 1: output log::

  received packet with src ip = 176.80.50.4 sent to queue 3
  received packet with src ip = 176.80.50.5 sent to queue 1
  received packet with src ip = 176.80.50.6 sent to queue 3
