Name

zones — Shorewall zone declaration file

Synopsis

/etc/shorewall/zones

Description

The /etc/shorewall/zones file declares your network zones. You specify the hosts in each zone through entries in /etc/shorewall/interfaces or /etc/shorewall/hosts.

The columns in the file are as follows.

ZONE - zone[:parent-zone[,parent-zone]...]

Name of the zone. The names "all", "none", "SOURCE" and "DEST" are reserved and may not be used as zone names. The maximum length of a zone name is determined by the setting of the LOGFORMAT option in shorewall.conf(5). With the default LOGFORMAT, zone names can be at most 5 characters long:

The maximum length of an iptables log prefix is 29 bytes. As explained in shorewall.conf (5), the default LOGPREFIX formatting string is “Shorewall:%s:%s:” where the first %s is replaced by the chain name and the second is replaced by the disposition.

  • The default formatting string has 12 fixed characters ("Shorewall" and three colons).

  • The longest of the standard dispositions are ACCEPT and REJECT which have 6 characters each.

  • The canonical name for the chain containing the rules for traffic going from zone 1 to zone 2 is "<zone 1>2<zone 2>".

  • So if M is the maximum zone name length, such chains can have length 2*M + 1.

    12 + 6 + 2*M + 1 = 29 which reduces to
    2*M = 29 - 12 - 6 - 1 = 10 or
    M = 5

The order in which Shorewall matches addresses from packets to zones is determined by the order of zone declarations. Where a zone is nested in one or more other zones, you may either ensure that the nested zone precedes its parents in this file, or you may follow the (sub)zone name by ":" and a comma-separated list of the parent zones. The parent zones must have been declared in earlier records in this file. See shorewall-nesting(5) for additional information.

Example:

#ZONE     TYPE     OPTIONS         IN OPTIONS        OUT OPTIONS
a         ipv4
b         ipv4
c:a,b     ipv4

Currently, Shorewall uses this information to reorder the zone list so that parent zones appear after their subzones in the list. The IMPLICIT_CONTINUE option in shorewall.conf(5) can also create implicit CONTINUE policies to/from the subzone.

In the future, Shorewall may make additional use of nesting information.

TYPE
ipv4

This is the standard Shorewall zone type and is the default if you leave this column empty or if you enter "-" in the column. Communication with some zone hosts may be encrypted. Encrypted hosts are designated using the 'ipsec'option in shorewall-hosts(5).

ipsec

Communication with all zone hosts is encrypted. Your kernel and iptables must include policy match support.

firewall

Designates the firewall itself. You must have exactly one 'firewall' zone. No options are permitted with a 'firewall' zone. The name that you enter in the ZONE column will be stored in the shell variable $FW which you may use in other configuration files to designate the firewall zone.

bport (or bport4)

(Shorewall-perl only) The zone is associated with one or more ports on a single bridge.

OPTIONS, IN OPTIONS and OUT OPTIONS - [option[,option]...]

A comma-separated list of options. With the exception of the mss option, these only apply to TYPE ipsec zones.

reqid=number

where number is specified using setkey(8) using the 'unique:number option for the SPD level.

spi=<number>

where number is the SPI of the SA used to encrypt/decrypt packets.

proto=ah|esp|ipcomp

IPSEC Encapsulation Protocol

mss=number

sets the MSS field in TCP packets. If you supply this option, you should also set FASTACCEPT=No in shorewall.conf(5) to insure that both the SYN and SYN,ACK packets have their MSS field adjusted.

mode=transport|tunnel

IPSEC mode

tunnel-src=address[/mask]

only available with mode=tunnel

tunnel-dst=address[/mask]

only available with mode=tunnel

strict

Means that packets must match all rules.

next

Separates rules; can only be used with strict

The options in the OPTIONS column are applied to both incoming and outgoing traffic. The IN OPTIONS are applied to incoming traffic (in addition to OPTIONS) and the OUT OPTIONS are applied to outgoing traffic.

If you wish to leave a column empty but need to make an entry in a following column, use "-".

FILES

/etc/shorewall/zones

See ALSO

http://www.shorewall.net/Multiple_Zones.html.

shorewall(8), shorewall-accounting(5), shorewall-actions(5), shorewall-blacklist(5), shorewall-hosts(5), shorewall-interfaces(5), shorewall-ipsec(5), shorewall-maclist(5), shorewall-masq(5), shorewall-nat(5), shorewall-nesting(8), shorewall-netmap(5), shorewall-params(5), shorewall-policy(5), shorewall-providers(5), shorewall-proxyarp(5), shorewall-route_rules(5), shorewall-routestopped(5), shorewall-rules(5), shorewall.conf(5), shorewall-tcclasses(5), shorewall-tcdevices(5), shorewall-tcrules(5), shorewall-tos(5), shorewall-tunnels(5)