Skip to content

Commit

Permalink
Merge pull request #1111 from nicolas-fort/nat_interfaces_group
Browse files Browse the repository at this point in the history 
NAT: add interface-group documentation.
  • Loading branch information
@rebortg
rebortg authored Oct 12, 2023
2 parents a7c0717 + 531c5b9 commit e0fa88b
Showing 1 changed file with 65 additions and 43 deletions.
108 changes: 65 additions & 43 deletions docs/configuration/nat/nat44.rst
View file
Original file line number Diff line number Diff line change
Expand Up @@ -148,23 +148,35 @@ rule.

* **outbound-interface** - applicable only to :ref:`source-nat`. It
configures the interface which is used for the outside traffic that
this translation rule applies to.
this translation rule applies to. Interface groups, inverted
selection and wildcard, are also supported.

Example:
Examples:

.. code-block:: none
set nat source rule 20 outbound-interface eth0
set nat source rule 20 outbound-interface interface-name eth0
set nat source rule 30 outbound-interface interface-name bond1*
set nat source rule 20 outbound-interface interface-name !vtun2
set nat source rule 20 outbound-interface interface-group GROUP1
set nat source rule 20 outbound-interface interface-group !GROUP2
* **inbound-interface** - applicable only to :ref:`destination-nat`. It
configures the interface which is used for the inside traffic the
translation rule applies to.
translation rule applies to. Interface groups, inverted
selection and wildcard, are also supported.

Example:

.. code-block:: none
set nat destination rule 20 inbound-interface eth1
set nat destination rule 20 inbound-interface interface-name eth0
set nat destination rule 30 inbound-interface interface-name bond1*
set nat destination rule 20 inbound-interface interface-name !vtun2
set nat destination rule 20 inbound-interface interface-group GROUP1
set nat destination rule 20 inbound-interface interface-group !GROUP2
* **protocol** - specify which types of protocols this translation rule
applies to. Only packets matching the specified protocol are NATed.
Expand Down Expand Up @@ -323,7 +335,7 @@ demonstrate the following configuration:

.. code-block:: none
set nat source rule 100 outbound-interface 'eth0'
set nat source rule 100 outbound-interface interface-name 'eth0'
set nat source rule 100 source address '192.168.0.0/24'
set nat source rule 100 translation address 'masquerade'
Expand All @@ -332,7 +344,9 @@ Which generates the following configuration:
.. code-block:: none
rule 100 {
outbound-interface eth0
outbound-interface {
interface-name eth0
}
source {
address 192.168.0.0/24
}
Expand Down Expand Up @@ -424,19 +438,19 @@ Example:
set nat destination rule 100 description 'Regular destination NAT from external'
set nat destination rule 100 destination port '3389'
set nat destination rule 100 inbound-interface 'pppoe0'
set nat destination rule 100 inbound-interface interface-name 'pppoe0'
set nat destination rule 100 protocol 'tcp'
set nat destination rule 100 translation address '192.0.2.40'
set nat destination rule 110 description 'NAT Reflection: INSIDE'
set nat destination rule 110 destination port '3389'
set nat destination rule 110 inbound-interface 'eth0.10'
set nat destination rule 110 inbound-interface interface-name 'eth0.10'
set nat destination rule 110 protocol 'tcp'
set nat destination rule 110 translation address '192.0.2.40'
set nat source rule 110 description 'NAT Reflection: INSIDE'
set nat source rule 110 destination address '192.0.2.0/24'
set nat source rule 110 outbound-interface 'eth0.10'
set nat source rule 110 outbound-interface interface-name 'eth0.10'
set nat source rule 110 protocol 'tcp'
set nat source rule 110 source address '192.0.2.0/24'
set nat source rule 110 translation address 'masquerade'
Expand All @@ -452,7 +466,9 @@ Which results in a configuration of:
destination {
port 3389
}
inbound-interface pppoe0
inbound-interface {
interface-name pppoe0
}
protocol tcp
translation {
address 192.0.2.40
Expand All @@ -463,7 +479,9 @@ Which results in a configuration of:
destination {
port 3389
}
inbound-interface eth0.10
inbound-interface {
interface-name eth0.10
}
protocol tcp
translation {
address 192.0.2.40
Expand All @@ -476,7 +494,9 @@ Which results in a configuration of:
destination {
address 192.0.2.0/24
}
outbound-interface eth0.10
outbound-interface {
interface-name eth0.10
}
protocol tcp
source {
address 192.0.2.0/24
Expand Down Expand Up @@ -515,7 +535,7 @@ Our configuration commands would be:
set nat destination rule 10 description 'Port Forward: HTTP to 192.168.0.100'
set nat destination rule 10 destination port '80'
set nat destination rule 10 inbound-interface 'eth0'
set nat destination rule 10 inbound-interface interface-name 'eth0'
set nat destination rule 10 protocol 'tcp'
set nat destination rule 10 translation address '192.168.0.100'
Expand All @@ -530,7 +550,9 @@ Which would generate the following NAT destination configuration:
destination {
port 80
}
inbound-interface eth0
inbound-interface {
interface-name eth0
}
protocol tcp
translation {
address 192.168.0.100
Expand All @@ -546,43 +568,45 @@ Which would generate the following NAT destination configuration:
This establishes our Port Forward rule, but if we created a firewall
policy it will likely block the traffic.

It is important to note that when creating firewall rules that the DNAT
Firewall rules for Destination NAT
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^

It is important to note that when creating firewall rules, the DNAT
translation occurs **before** traffic traverses the firewall. In other
words, the destination address has already been translated to
192.168.0.100.

So in our firewall policy, we want to allow traffic coming in on the
outside interface, destined for TCP port 80 and the IP address of
192.168.0.100.
So in our firewall ruleset, we want to allow traffic which previously matched
a destination nat rule. In order to avoid creating many rules, one for each
destination nat rule, we can accept all **'dnat'** connections with one simple
rule, using ``connection-status`` matcher:

.. code-block:: none
set firewall name OUTSIDE-IN rule 20 action 'accept'
set firewall name OUTSIDE-IN rule 20 destination address '192.168.0.100'
set firewall name OUTSIDE-IN rule 20 destination port '80'
set firewall name OUTSIDE-IN rule 20 protocol 'tcp'
set firewall name OUTSIDE-IN rule 20 state new 'enable'
set firewall ipv4 forward filter rule 10 action accept
set firewall ipv4 forward filter rule 10 connection-status nat destination
set firewall ipv4 forward filter rule 10 state new enable
This would generate the following configuration:

.. code-block:: none
rule 20 {
action accept
destination {
address 192.168.0.100
port 80
}
protocol tcp
state {
new enable
ipv4 {
forward {
filter {
rule 10 {
action accept
connection-status {
nat destination
}
state {
new enable
}
}
}
}
}
.. note::

If you have configured the `INSIDE-OUT` policy, you will need to add
additional rules to permit inbound NAT traffic.
1-to-1 NAT
----------
Expand Down Expand Up @@ -610,10 +634,10 @@ and one external interface:
set interfaces ethernet eth1 description 'Outside interface'
set nat destination rule 2000 description '1-to-1 NAT example'
set nat destination rule 2000 destination address '192.0.2.30'
set nat destination rule 2000 inbound-interface 'eth1'
set nat destination rule 2000 inbound-interface interface-name 'eth1'
set nat destination rule 2000 translation address '192.168.1.10'
set nat source rule 2000 description '1-to-1 NAT example'
set nat source rule 2000 outbound-interface 'eth1'
set nat source rule 2000 outbound-interface interface-name 'eth1'
set nat source rule 2000 source address '192.168.1.10'
set nat source rule 2000 translation address '192.0.2.30'
Expand All @@ -639,7 +663,7 @@ We will use source and destination address for hash generation.

.. code-block:: none
set nat destination rule 10 inbound-interface eth0
set nat destination rule 10 inbound-interface inbound-interface eth0
set nat destination rule 10 protocol tcp
set nat destination rule 10 destination port 80
set nat destination rule 10 load-balance hash source-address
Expand All @@ -655,7 +679,7 @@ We will generate the hash randomly.

.. code-block:: none
set nat source rule 10 outbound-interface eth0
set nat source rule 10 outbound-interface interface-name eth0
set nat source rule 10 source address 10.0.0.0/8
set nat source rule 10 load-balance hash random
set nat source rule 10 load-balance backend 192.0.2.251 weight 33
Expand Down Expand Up @@ -709,12 +733,10 @@ NAT Configuration
set nat source rule 110 description 'Internal to ASP'
set nat source rule 110 destination address '172.27.1.0/24'
set nat source rule 110 outbound-interface 'any'
set nat source rule 110 source address '192.168.43.0/24'
set nat source rule 110 translation address '172.29.41.89'
set nat source rule 120 description 'Internal to ASP'
set nat source rule 120 destination address '10.125.0.0/16'
set nat source rule 120 outbound-interface 'any'
set nat source rule 120 source address '192.168.43.0/24'
set nat source rule 120 translation address '172.29.41.89'
Expand Down

0 comments on commit e0fa88b

Please sign in to comment.