#
# Shorewall version 4 - Interfaces File
#
# For information about entries in this file, type "man shorewall-interfaces"
#
# The manpage is also online at
# https://shorewall.org/manpages/shorewall-interfaces.html
#
###############################################################################
# 
# The interfaces file serves to define the firewall's network interfaces to
# Shorewall. The order of entries in this file is not significant in determining
# zone composition.
# 
# Beginning with Shorewall 4.5.3, the interfaces file supports two different
# formats:
# 
# FORMAT 1 (default - deprecated)
# 
#     There is a BROADCAST column which can be used to specify the broadcast
#     address associated with the interface.
# 
# FORMAT 2
# 
#     The BROADCAST column is omitted.
# 
# The format is specified by a line as follows:
# 
#     ?FORMAT {1|2}
# 
# The columns in the file are as follows.
# 
# ZONE - zone-name
# 
#     Zone for this interface. Must match the name of a zone declared in /etc/
#     shorewall/zones. You may not list the firewall zone in this column.
# 
#     If the interface serves multiple zones that will be defined in the
#     shorewall-hosts(5) file, you should place "-" in this column.
# 
#     If there are multiple interfaces to the same zone, you must list them in
#     separate entries.
# 
#     Example:
# 
#         #ZONE   INTERFACE       BROADCAST
#         loc     eth1            -
#         loc     eth2            -
# 
# INTERFACE - interface[:port]
# 
#     Logical name of interface. Each interface may be listed only once in this
#     file. You may NOT specify the name of a "virtual" interface (e.g., eth0:0)
#     here; see https://shorewall.org/FAQ.htm#faq18. If the physical option is
#     not specified, then the logical name is also the name of the actual
#     interface.
# 
#     You may use wildcards here by specifying a prefix followed by the plus sign
#     ("+"). For example, if you want to make an entry that applies to all PPP
#     interfaces, use 'ppp+'; that would match ppp0, ppp1, ppp2, …
# 
#     When using Shorewall versions before 4.1.4, care must be exercised when
#     using wildcards where there is another zone that uses a matching specific
#     interface. See shorewall-nesting(5) for a discussion of this problem.
# 
#     Shorewall allows '+' as an interface name, but that usage is deprecated. A
#     better approach is to specify 'physical=+' in the OPTIONS column (see
#     below).
# 
#     There is no need to define the loopback interface (lo) in this file.
# 
#     If a port is given, then the interface must have been defined previously
#     with the bridge option. The OPTIONS column may not contain the following
#     options when a port is given.
# 
#     arp_filter
#     arp_ignore
#     bridge
#     log_martians
#     mss
#     optional
#     proxyarp
#     required
#     routefilter
#     sourceroute
#     upnp
#     wait
# 
#     Beginning with Shorewall 4.5.17, if you specify a zone for the 'lo'
#     interface, then that zone must be defined as type local in shorewall6-zones
#     (5).
# 
# BROADCAST (Optional) - {-|detect|address[,address]...}
# 
#     Only available if FORMAT 1.
# 
#     If you use the special value detect, Shorewall will detect the broadcast
#     address(es) for you if your iptables and kernel include Address Type Match
#     support.
# 
#     If your iptables and/or kernel lack Address Type Match support then you may
#     list the broadcast address(es) for the network(s) to which the interface
#     belongs. For P-T-P interfaces, this column is left blank. If the interface
#     has multiple addresses on multiple subnets then list the broadcast
#     addresses as a comma-separated list.
# 
#     If you don't want to give a value for this column but you want to enter a
#     value in the OPTIONS column, enter - in this column.
# 
# OPTIONS (Optional) - [option[,option]...]
# 
#     A comma-separated list of options from the following list. The order in
#     which you list the options is not significant but the list should have no
#     embedded white-space.
# 
#     accept_ra[={0|1|2}]
# 
#         IPv6 only; added in Shorewall 4.5.16. Values are:
# 
#         0
# 
#             Do not accept Router Advertisements.
# 
#         1
# 
#             Accept Route Advertisements if forwarding is disabled.
# 
#         2
# 
#             Overrule forwarding behavior. Accept Route Advertisements even if
#             forwarding is enabled.
# 
#         If the option is specified without a value, then the value 1 is
#         assumed.
# 
#         Note
# 
#         This option does not work with a wild-card physical name (e.g.,
#         eth0.+). Beginning with Shorewall 5.1.10, If this option is specified,
#         a warning is issued and the option is ignored.
# 
#     arp_filter[={0|1}]
# 
#         IPv4 only. If specified, this interface will only respond to ARP
#         who-has requests for IP addresses configured on the interface. If not
#         specified, the interface can respond to ARP who-has requests for IP
#         addresses on any of the firewall's interface. The interface must be up
#         when Shorewall is started.
# 
#         Only those interfaces with the arp_filter option will have their
#         setting changed; the value assigned to the setting will be the value
#         specified (if any) or 1 if no value is given.
# 
#         Note
# 
#         This option does not work with a wild-card physical name (e.g.,
#         eth0.+). Beginning with Shorewall 5.1.10, If this option is specified,
#         a warning is issued and the option is ignored.
# 
#     arp_ignore[=number]
# 
#         IPv4 only. If specified, this interface will respond to arp requests
#         based on the value of number (defaults to 1).
# 
#         1 - reply only if the target IP address is local address configured on
#         the incoming interface
# 
#         2 - reply only if the target IP address is local address configured on
#         the incoming interface and the sender's IP address is part from same
#         subnet on this interface's address
# 
#         3 - do not reply for local addresses configured with scope host, only
#         resolutions for global and link
# 
#         4-7 - reserved
# 
#         8 - do not reply for all local addresses
# 
#         Note
# 
#         This option does not work with a wild-card physical name (e.g.,
#         eth0.+). Beginning with Shorewall 5.1.10, If this option is specified,
#         a warning is issued and the option is ignored.
# 
#         Warning
# 
#         Do not specify arp_ignore for any interface involved in Proxy ARP.
# 
#     blacklist
# 
#         Checks packets arriving on this interface against the
#         shorewall-blacklist(5) file.
# 
#         Beginning with Shorewall 4.4.13:
# 
#           ☆ If a zone is given in the ZONES column, then the behavior is as if 
#             blacklist had been specified in the IN_OPTIONS column of
#             shorewall-zones(5).
# 
#           ☆ Otherwise, the option is ignored with a warning:
# 
#                 WARNING: The 'blacklist' option is ignored on multi-zone
#                 interfaces
# 
#     bridge
# 
#         Designates the interface as a bridge. Beginning with Shorewall 4.4.7,
#         setting this option also sets routeback.
# 
#         Note
# 
#         If you have a bridge that you don't intend to define bport zones on,
#         then it is best to omit this option and simply specify routeback.
# 
#     dbl={none|src|dst|src-dst}
# 
#         Added in Shorewall 5.0.10. This option defined whether or not dynamic
#         blacklisting is applied to packets entering the firewall through this
#         interface and whether the source address and/or destination address is
#         to be compared against the ipset-based dynamic blacklist
#         (DYNAMIC_BLACKLIST=ipset... in shorewall.conf(5)). The default is
#         determine by the setting of DYNAMIC_BLACKLIST:
# 
#         DYNAMIC_BLACKLIST=No
# 
#             Default is none (e.g., no dynamic blacklist checking).
# 
#         DYNAMIC_BLACKLIST=Yes
# 
#             Default is src (e.g., the source IP address is checked).
# 
#         DYNAMIC_BLACKLIST=ipset[-only]
# 
#             Default is src.
# 
#         DYNAMIC_BLACKLIST=ipset[-only],src-dst...
# 
#             Default is src-dst (e.g., the source IP addresses in checked
#             against the ipset on input and the destination IP address is
#             checked against the ipset on packets originating from the firewall
#             and leaving through this interface).
# 
#         The normal setting for this option will be dst or none for internal
#         interfaces and src or src-dst for Internet-facing interfaces.
# 
#     destonly
# 
#         Added in Shorewall 4.5.17. Causes the compiler to omit rules to handle
#         traffic from this interface.
# 
#     dhcp
# 
#         Specify this option when any of the following are true:
# 
#          1. the interface gets its IP address via DHCP
# 
#          2. the interface is used by a DHCP server running on the firewall
# 
#          3. the interface has a static IP but is on a LAN segment with lots of
#             DHCP clients.
# 
#          4. the interface is a simple bridge with a DHCP server on one port and
#             DHCP clients on another port.
# 
#             Note
# 
#             If you use Shorewall-perl for firewall/bridging, then you need to
#             include DHCP-specific rules in shorewall-rules(5). DHCP uses UDP
#             ports 67 and 68.
# 
#         This option allows DHCP datagrams to enter and leave the interface.
# 
#     forward[={0|1}]
# 
#         IPv6 only Sets the /proc/sys/net/ipv6/conf/interface/forwarding option
#         to the specified value. If no value is supplied, then 1 is assumed.
# 
#         Note
# 
#         This option does not work with a wild-card physical name (e.g.,
#         eth0.+). Beginning with Shorewall 5.1.10, If this option is specified,
#         a warning is issued and the option is ignored.
# 
#     ignore[=1]
# 
#         When specified, causes the generated script to ignore up/down events
#         from Shorewall-init for this device. Additionally, the option exempts
#         the interface from hairpin filtering. When '=1' is omitted, the ZONE
#         column must contain '-' and ignore must be the only OPTION.
# 
#         Beginning with Shorewall 4.5.5, may be specified as 'ignore=1' which
#         only causes the generated script to ignore up/down events from
#         Shorewall-init; hairpin filtering is still applied. In this case, the
#         above restrictions on the ZONE and OPTIONS columns are lifted.
# 
#     loopback
# 
#         Added in Shorewall 4.6.6. Designates the interface as the loopback
#         interface. This option is assumed if the interface's physical name is
#         'lo'. Only one interface man have the loopback option specified.
# 
#     logmartians[={0|1}]
# 
#         IPv4 only. Turn on kernel martian logging (logging of packets with
#         impossible source addresses. It is strongly suggested that if you set 
#         routefilter on an interface that you also set logmartians. Even if you
#         do not specify the routefilter option, it is a good idea to specify
#         logmartians because your distribution may have enabled route filtering
#         without you knowing it.
# 
#         Only those interfaces with the logmartians option will have their
#         setting changed; the value assigned to the setting will be the value
#         specified (if any) or 1 if no value is given.
# 
#         To find out if route filtering is set on a given interface, check the
#         contents of /proc/sys/net/ipv4/conf/interface/rp_filter - a non-zero
#         value indicates that route filtering is enabled.
# 
#         Example:
# 
#                 teastep@lists:~$ cat /proc/sys/net/ipv4/conf/eth0/rp_filter 
#                 1
#                 teastep@lists:~$
# 
#         Note
# 
#         This option does not work with a wild-card physical name (e.g.,
#         eth0.+). Beginning with Shorewall 5.1.10, If this option is specified,
#         a warning is issued and the option is ignored.
# 
#             This option may also be enabled globally in the shorewall.conf(5)
#             file.
# 
#     maclist
# 
#         Connection requests from this interface are compared against the
#         contents of shorewall-maclist(5). If this option is specified, the
#         interface must be an Ethernet NIC and must be up before Shorewall is
#         started.
# 
#     mss=number
# 
#         Added in Shorewall 4.0.3. Causes forwarded TCP SYN packets entering or
#         leaving on this interface to have their MSS field set to the specified
#         number.
# 
#     nets=(net[,...])
# 
#         Limit the zone named in the ZONE column to only the listed networks.
#         The parentheses may be omitted if only a single net is given (e.g.,
#         nets=192.168.1.0/24). Limited broadcast to the zone is supported.
#         Beginning with Shorewall 4.4.1, multicast traffic to the zone is also
#         supported.
# 
#     nets=dynamic
# 
#         Defines the zone as dynamic. Requires ipset match support in your
#         iptables and kernel. See https://shorewall.org/Dynamic.html for further
#         information.
# 
#     nodbl
# 
#         Added in Shorewall 5.0.8. When specified, dynamic blacklisting is
#         disabled on the interface. Beginning with Shorewall 5.0.10, nodbl is
#         equivalent to dbl=none.
# 
#     nosmurfs
# 
#         IPv4 only. Filter packets for smurfs (packets with a broadcast address
#         as the source).
# 
#         Smurfs will be optionally logged based on the setting of
#         SMURF_LOG_LEVEL in shorewall.conf(5). After logging, the packets are
#         dropped.
# 
#     optional
# 
#         This option indicates that the firewall should be able to start, even
#         if the interface is not usable for handling traffic. It allows use of
#         the enable and disable commands on the interface.
# 
#         When optional is specified for an interface, Shorewall will be silent
#         when:
# 
#           ☆ a /proc/sys/net/ipv[46]/conf/ entry for the interface cannot be
#             modified (including for proxy ARP or proxy NDP).
# 
#           ☆ The first address of the interface cannot be obtained.
# 
#           ☆ The gateway of the interface can not be obtained (provider
#             interface).
# 
#           ☆ The interface has been disabled using the disable command.
# 
#         May not be specified with required.
# 
#     physical=name
# 
#         Added in Shorewall 4.4.4. When specified, the interface or port name in
#         the INTERFACE column is a logical name that refers to the name given in
#         this option. It is useful when you want to specify the same wildcard
#         port name on two or more bridges. See https://shorewall.org/
#         bridge-Shorewall-perl.html#Multiple.
# 
#         If the interface name is a wildcard name (ends with '+'), then the
#         physical name must also end in '+'. The physical name may end in '+'
#         (or be exactly '+') when the interface name is not a wildcard name.
# 
#         If physical is not specified, then it's value defaults to the interface
#         name.
# 
#     proxyarp[={0|1}]
# 
#         IPv4 only. Sets /proc/sys/net/ipv4/conf/interface/proxy_arp. Do NOT use
#         this option if you are employing Proxy ARP through entries in
#         shorewall-proxyarp(5). This option is intended solely for use with
#         Proxy ARP sub-networking as described at: http://tldp.org/HOWTO/
#         Proxy-ARP-Subnet/index.html.
# 
#         Note
# 
#         This option does not work with a wild-card physical name (e.g.,
#         eth0.+). Beginning with Shorewall 5.1.10, If this option is specified,
#         a warning is issued and the option is ignored.
# 
#         Only those interfaces with the proxyarp option will have their setting
#         changed; the value assigned to the setting will be the value specified
#         (if any) or 1 if no value is given.
# 
#     proxyndp[={0|1}]
# 
#         IPv6 only. Sets /proc/sys/net/ipv6/conf/interface/proxy_ndp.
# 
#         Note
# 
#         This option does not work with a wild-card physical name (e.g.,
#         eth0.+). Beginning with Shorewall 5.1.10, If this option is specified,
#         a warning is issued and the option is ignored.
# 
#         Only those interfaces with the proxyndp option will have their setting
#         changed; the value assigned to the setting will be the value specified
#         (if any) or 1 if no value is given.
# 
#     required
# 
#         Added in Shorewall 4.4.10. If this option is set, the firewall will
#         fail to start if the interface is not usable. May not be specified
#         together with optional.
# 
#     routeback[={0|1}]
# 
#         If specified, indicates that Shorewall should include rules that allow
#         traffic arriving on this interface to be routed back out that same
#         interface. This option is also required when you have used a wildcard
#         in the INTERFACE column if you want to allow traffic between the
#         interfaces that match the wildcard.
# 
#         Beginning with Shorewall 4.4.20, if you specify this option, then you
#         should also specify either sfilter (see below) or routefilter on all
#         interfaces (see below).
# 
#         Beginning with Shorewall 4.5.18, you may specify this option to
#         explicitly reset (e.g., routeback=0). This can be used to override
#         Shorewall's default setting for bridge devices which is routeback=1.
# 
#     routefilter[={0|1|2}]
# 
#         IPv4 only. Turn on kernel route filtering for this interface
#         (anti-spoofing measure).
# 
#         Only those interfaces with the routefilter option will have their
#         setting changes; the value assigned to the setting will be the value
#         specified (if any) or 1 if no value is given.
# 
#         The value 2 is only available with Shorewall 4.4.5.1 and later when the
#         kernel version is 2.6.31 or later. It specifies a loose form of reverse
#         path filtering.
# 
#         Note
# 
#         This option does not work with a wild-card physical name (e.g.,
#         eth0.+). Beginning with Shorewall 5.1.10, If this option is specified,
#         a warning is issued and the option is ignored.
# 
#         This option can also be enabled globally via the ROUTE_FILTER option in
#         the shorewall.conf(5) file.
# 
#         Important
# 
#         If ROUTE_FILTER=Yes in shorewall.conf(5), or if your distribution sets
#         net.ipv4.conf.all.rp_filter=1 in /etc/sysctl.conf, then setting 
#         routefilter=0 in an interface entry will not disable route filtering on
#         that interface! The effective setting for an interface is the maximum
#         of the contents of /proc/sys/net/ipv4/conf/all/rp_filter and the
#         routefilter setting specified in this file (/proc/sys/net/ipv4/conf/
#         interface/rp_filter).
# 
#         Note
# 
#         There are certain cases where routefilter cannot be used on an
#         interface:
# 
#           ☆ If USE_DEFAULT_RT=Yes in shorewall.conf(5) and the interface is
#             listed in shorewall-providers(5).
# 
#           ☆ If there is an entry for the interface in shorewall-providers(5)
#             that doesn't specify the balance option.
# 
#           ☆ If IPSEC is used to allow a road-warrior to have a local address,
#             then any interface through which the road-warrior might connect
#             cannot specify routefilter.
# 
#         Beginning with Shorewall 5.1.1, when routefilter is set to a non-zero
#         value, the logmartians option is also implicitly set. If you actually
#         want route filtering without logging, then you must also specify
#         logmartians=0 after routefilter.
# 
#     rpfilter
# 
#         Added in Shorewall 4.5.7. This is an anti-spoofing measure that
#         requires the 'RPFilter Match' capability in your iptables and kernel.
#         It provides a more efficient alternative to the sfilter option below.
#         It performs a function similar to routefilter (see above) but works
#         with Multi-ISP configurations that do not use balanced routes.
# 
#     sfilter=(net[,...])
# 
#         Added in Shorewall 4.4.20. This option provides an anti-spoofing
#         alternative to routefilter on interfaces where that option cannot be
#         used, but where the routeback option is required (on a bridge, for
#         example). On these interfaces, sfilter should list those local networks
#         that are connected to the firewall through other interfaces.
# 
#     sourceroute[={0|1}]
# 
#         If this option is not specified for an interface, then source-routed
#         packets will not be accepted from that interface unless it has been
#         explicitly enabled via sysconf. Only set this option to 1 (enable
#         source routing) if you know what you are doing. This might represent a
#         security risk and is usually unneeded.
# 
#         Only those interfaces with the sourceroute option will have their
#         setting changed; the value assigned to the setting will be the value
#         specified (if any) or 1 if no value is given.
# 
#         Note
# 
#         This option does not work with a wild-card physical name (e.g.,
#         eth0.+). Beginning with Shorewall 5.1.10, If this option is specified,
#         a warning is issued and the option is ignored.
# 
#     tcpflags[={0|1}]
# 
#         Packets arriving on this interface are checked for certain illegal
#         combinations of TCP flags. Packets found to have such a combination of
#         flags are handled according to the setting of TCP_FLAGS_DISPOSITION
#         after having been logged according to the setting of
#         TCP_FLAGS_LOG_LEVEL.
# 
#         Beginning with Shorewall 4.6.0, tcpflags=1 is the default. To disable
#         this option, specify tcpflags=0.
# 
#     unmanaged
# 
#         Added in Shorewall 4.5.18. Causes all traffic between the firewall and
#         hosts on the interface to be accepted. When this option is given:
# 
#           ☆ The ZONE column must contain '-'.
# 
#           ☆ Only the following other options are allowed with unmanaged:
# 
#             arp_filter
#             arp_ignore
#             ignore
#             routefilter
#             optional
#             physical
#             routefilter
#             proxyarp
#             proxyudp
#             sourceroute
# 
#     upnp
# 
#         Incoming requests from this interface may be remapped via UPNP (upnpd).
#         See https://shorewall.org/UPnP.html. Supported in IPv4 and in IPv6 in
#         Shorewall 5.1.4 and later.
# 
#     upnpclient
# 
#         This option is intended for laptop users who always run Shorewall on
#         their system yet need to run UPnP-enabled client apps such as
#         Transmission (BitTorrent client). The option causes Shorewall to detect
#         the default gateway through the interface and to accept UDP packets
#         from that gateway. Note that, like all aspects of UPnP, this is a
#         security hole so use this option at your own risk. Supported in IPv4
#         and in IPv6 in Shorewall 5.1.4 and later.
# 
#     wait=seconds
# 
#         Added in Shorewall 4.4.10. Causes the generated script to wait up to 
#         seconds seconds for the interface to become usable before applying the 
#         required or optional options.
# 
# Example
# 
# IPv4 Example 1:
# 
#     Suppose you have eth0 connected to a DSL modem and eth1 connected to your
#     local network and that your local subnet is 192.168.1.0/24. The interface
#     gets its IP address via DHCP from subnet 206.191.149.192/27. You have a DMZ
#     with subnet 192.168.2.0/24 using eth2. Your iptables and/or kernel do not
#     support "Address Type Match" and you prefer to specify broadcast addresses
#     explicitly rather than having Shorewall detect them.
# 
#     Your entries for this setup would look like:
# 
#     ?FORMAT 1
#     #ZONE   INTERFACE BROADCAST        OPTIONS
#     net     eth0      206.191.149.223  dhcp
#     loc     eth1      192.168.1.255
#     dmz     eth2      192.168.2.255
# 
# Example 2:
# 
#     The same configuration without specifying broadcast addresses is:
# 
#     ?FORMAT 2
#     #ZONE   INTERFACE OPTIONS
#     net     eth0      dhcp
#     loc     eth1
#     dmz     eth2
# 
# Example 3:
# 
#     You have a simple dial-in system with no Ethernet connections.
# 
#     ?FORMAT 2
#     #ZONE   INTERFACE OPTIONS
#     net     ppp0      -
# 
# Example 4 (Shorewall 4.4.9 and later):
# 
#     You have a bridge with no IP address and you want to allow traffic through
#     the bridge.
# 
#     ?FORMAT 2
#     #ZONE   INTERFACE OPTIONS
#     -       br0       bridge
# 
###############################################################################
?FORMAT 2
###############################################################################
#ZONE	INTERFACE	OPTIONS
-	lo		ignore
net	all		dhcp,physical=+,routeback
