================
Traffic Selector
================

.. sidebar:: Contents

  .. contents::
      :depth: 2
      :local:


This chapter covers some aspects related to ``traffic selector``,
which is a set of rules that allows us to filter network packets
based on different attributes: incoming/outgoing interface,
source/destination address, protocol, VRF, etc.

``traffic selectors`` behaves like ACLs (Access Control Lists) and
can be used in many places in configuration; such as, ``traffic
policies``, ``NAT``, ``Netflow``, ``traffic trace``, etc.


Every ``traffic selector`` contains a set of rules that are processed
in order until one of them matches the current network packet. The
sense of matching can be inverted by using the ``not`` command. The
special ``exclude`` command can be used to stop checking remaining rules
if current one matches.

.. note::
   Rules are evaluated in ascending order. Meaning that, if first rule
   is met, the remaining rules are not evaluated and network packet is
   selected. As a reminder, ``exclude`` is an exception: if a rule with
   the ``exclude`` command matches, the remanining rules are not evaluated
   and packet is not selected.


Configuration
=============

This is the syntax to create a ``traffic selector``:

.. code-block:: none

  set traffic selector <selector_name> [ ... ]

In order to attach a ``traffic selector`` in a ``traffic policy rule``
you can use the following command:

.. code-block:: none

  set traffic policy <policy_name> rule <u32> selector <selector_name>

And, in the case of an interface with NAT:

.. code-block:: none

  set interfaces <if_type> <if_name> traffic nat <source / destination> rule <u32> selector <selector_name>


Below, you can find the different fitlers available. *Network family* refers to the network layer where this filter will act:

 - ARP filters act on level 2.
 - IPv4 / IPv6 filters act on level 3.

Inet refers to both IPv4 & IPv6 filters.
The filters that do not have a specific *Network family* is because the match is based on some metadata information (e.g., the packet input interface).

The *compatible features* column refers to the OSDx features where a specific traffic selector filter can be used.

.. dropdown:: **Available filters**:

  +-------------------------+----------------+---------------------------------+
  | Traffic selector filter | Network family | Compatible features             |
  +=========================+================+=================================+
  | advisor                 |                | All                             |
  +-------------------------+----------------+---------------------------------+
  | app-id                  | Inet           | Regular policies, NAT & Netflow |
  +-------------------------+----------------+---------------------------------+
  | arp-operation           | ARP            | Link policy                     |
  +-------------------------+----------------+---------------------------------+
  | connmark                |                | Regular policies, NAT & Netflow |
  +-------------------------+----------------+---------------------------------+
  | destination             | Inet / ARP     | All                             |
  +-------------------------+----------------+---------------------------------+
  | dscp                    | IPv4           | All, except IPv6                |
  +-------------------------+----------------+---------------------------------+
  | ecn                     | IPv4           | All, except IPv6                |
  +-------------------------+----------------+---------------------------------+
  | ether-type              | ARP            | Link policy                     |
  +-------------------------+----------------+---------------------------------+
  | extra-connmark          |                | Regular policies, NAT & Netflow |
  +-------------------------+----------------+---------------------------------+
  | extra-mark              |                | Regular policies, NAT & Netflow |
  +-------------------------+----------------+---------------------------------+
  | fragmentation           | IPv4           | All, except IPv6                |
  +-------------------------+----------------+---------------------------------+
  | header-length           | IPv4           | All, except IPv6                |
  +-------------------------+----------------+---------------------------------+
  | hoplimit                | IPv6           | All, except IPv4                |
  +-------------------------+----------------+---------------------------------+
  | icmp-code               | IPv4           | All, except IPv6                |
  +-------------------------+----------------+---------------------------------+
  | icmp-type               | IPv4           | All, except IPv6                |
  +-------------------------+----------------+---------------------------------+
  | in-interface            |                | All                             |
  +-------------------------+----------------+---------------------------------+
  | ip-option               | IPv4           | All, except IPv6                |
  +-------------------------+----------------+---------------------------------+
  | ipv6-dscp               | IPv6           | All, except IPv4                |
  +-------------------------+----------------+---------------------------------+
  | ipv6-ecn                | IPv6           | All, except IPv4                |
  +-------------------------+----------------+---------------------------------+
  | ipv6-extension          | IPv6           | All, except IPv4                |
  +-------------------------+----------------+---------------------------------+
  | ipv6-fragmentation      | IPv6           | All, except IPv4                |
  +-------------------------+----------------+---------------------------------+
  | ipv6-icmp-code          | IPv6           | All, except IPv4                |
  +-------------------------+----------------+---------------------------------+
  | ipv6-icmp-type          | IPv6           | All, except IPv4                |
  +-------------------------+----------------+---------------------------------+
  | ipv6-next-header        | IPv6           | All, except IPv4                |
  +-------------------------+----------------+---------------------------------+
  | label                   |                | Regular policies, NAT & Netflow |
  +-------------------------+----------------+---------------------------------+
  | length                  | ARP            | All                             |
  +-------------------------+----------------+---------------------------------+
  | mark                    |                | Regular policies, NAT & Netflow |
  +-------------------------+----------------+---------------------------------+
  | ori-in-interface        |                | All                             |
  +-------------------------+----------------+---------------------------------+
  | out-interface           |                | All                             |
  +-------------------------+----------------+---------------------------------+
  | pkt-type                | ARP            | All                             |
  +-------------------------+----------------+---------------------------------+
  | protocol                | Inet           | All                             |
  +-------------------------+----------------+---------------------------------+
  | source                  | Inet / ARP     | All                             |
  +-------------------------+----------------+---------------------------------+
  | state                   |                | Regular policies, NAT & Netflow |
  +-------------------------+----------------+---------------------------------+
  | tcp-flags               | Inet           | All                             |
  +-------------------------+----------------+---------------------------------+
  | tcp-mss                 | Inet           | All                             |
  +-------------------------+----------------+---------------------------------+
  | tcp-option              | Inet           | All                             |
  +-------------------------+----------------+---------------------------------+
  | tcp-window              | Inet           | All                             |
  +-------------------------+----------------+---------------------------------+
  | ttl                     | IPv4           | All, except IPv6                |
  +-------------------------+----------------+---------------------------------+
  | vrf-connmark            |                | Regular policies, NAT & Netflow |
  +-------------------------+----------------+---------------------------------+
  | vrf-mark                |                | Regular policies, NAT & Netflow |
  +-------------------------+----------------+---------------------------------+


Examples
========

Let's suppose we need to control the network packets that
meet one of the following conditions:

  * Source address is one of the addresses specified in ADDR_LAN group (click
    :doc:`here <../group/index>` for more information about ``traffic groups``).
  * Protocol is tcp and destination port is 80 or 443.
  * Protocol is icmp or udp and destination address is not 10.0.0.0/24.

In order to filter the network packets that meet those constraints, you can create
the following ``traffic selector``:

.. code-block:: none

  set traffic selector SEL_LAN rule 1 source address-group ADDR_LAN
  set traffic selector SEL_LAN rule 2 protocol tcp
  set traffic selector SEL_LAN rule 2 destination port 80,443
  set traffic selector SEL_LAN rule 3 protocol icmp,udp
  set traffic selector SEL_LAN rule 3 not destination address 10.0.0.0/24


:ref:`Here <example_traffic_selector_selector>`, you can find more examples related
to ``traffic selector``.


Monitoring
==========

The operational command :osdx:op:`traffic selector * show` can be used to
display some network statistics.

*Example:*

.. code-block:: none

  admin@osdx$ traffic selector SEL_SUBNET2 show
  Selector SEL_SUBNET2 (nat destination -- ifc eth1 -- rule 1)

  -----------------------------------------------------
  rule   pkts match  pkts eval  bytes match  bytes eval
  -----------------------------------------------------
  1               2          2          106         106
  -----------------------------------------------------
  Total           2          2          106         106


Command Summary
===============

.. osdx:cmdtree:: cfg
  :maxdepth: 4

  traffic selector

.. osdx:cmdtree:: op

  traffic selector