shorewall-hosts(5)
NAME
hosts - Shorewall file
SYNOPSIS
/etc/shorewall/hosts
DESCRIPTION
This file is used to define zones in terms of subnets and/or individual
IP addresses. Most simple setups don't need to (should not) place
anything in this file.
The order of entries in this file is not significant in determining
zone composition. Rather, the order that the zones are declared in
shorewall-zones[1](5) determines the order in which the records in this
file are interpreted.
Warning
The only time that you need this file is when you have more than
one zone connected through a single interface.
Warning
If you have an entry for a zone and interface in
shorewall-interfaces[2](5) then do not include any entries in this
file for that same (zone, interface) pair.
The columns in the file are as follows.
ZONE - zone-name
The name of a zone declared in shorewall-zones[1](5). You may not
list the firewall zone in this column.
HOST(S) -
interface:{[{address-or-range[,address-or-range]...|+ipset|dynamic}[exclusion]
The name of an interface defined in the shorewall-interfaces[2](5)
file followed by a colon (":") and a comma-separated list whose
elements are either:
1. The IP address of a host.
2. A network in CIDR format.
3. An IP address range of the form low.address-high.address. Your
kernel and iptables must have iprange match support.
4. The name of an ipset.
5. The word dynamic which makes the zone dynamic in that you can
use the shorewall add and shorewall delete commands to change
to composition of the zone.
You may also exclude certain hosts through use of an exclusion (see
shorewall-exclusion[3](5).
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
must have no embedded white-space.
blacklist
Check packets arriving on this port against the
shorewall-blacklist[4](5) file.
broadcast
Used when you want to include limited broadcasts (destination
IP address 255.255.255.255) from the firewall to this zone.
Only necessary when:
1. The network specified in the HOST(S) column does not
include 255.255.255.255.
2. The zone does not have an entry for this interface in
shorewall-interfaces[2](5).
destonly
Normally used with the Multi-cast IP address range
(224.0.0.0/4). Specifies that traffic will be sent to the
specified net(s) but that no traffic will be received from the
net(s).
ipsec
The zone is accessed via a kernel 2.6 ipsec SA. Note that if
the zone named in the ZONE column is specified as an IPSEC zone
in the shorewall-zones[1](5) file then you do NOT need to
specify the 'ipsec' option here.
maclist
Connection requests from these hosts are compared against the
contents of shorewall-maclist[5](5). If this option is
specified, the interface must be an Ethernet NIC or equivalent
and must be up before Shorewall is started.
mss=mss
Added in Shorewall 4.5.2. When present, causes the TCP mss for
new connections to/from the hosts given in the HOST(S) column
to be clamped at the specified mss.
nosmurfs
This option only makes sense for ports on a bridge.
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[6](5). After logging, the
packets are dropped.
routeback
Shorewall should set up the infrastructure to pass packets from
this/these address(es) back to themselves. This is necessary if
hosts in this group use the services of a transparent proxy
that is a member of the group or if DNAT is used to send
requests originating from this group to a server in the group.
tcpflags
Packets arriving from these hosts 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.
EXAMPLES
Example 1
The firewall runs a PPTP server which creates a ppp interface for
each remote client. The clients are assigned IP addresses in the
network 192.168.3.0/24 and in a zone named 'vpn'.
#ZONE HOST(S) OPTIONS
vpn ppp+:192.168.3.0/24
FILES
/etc/shorewall/hosts
SEE ALSO
http://www.shorewall.net/configuration_file_basics.htm#Pairs[7] shorewall(8), shorewall-accounting(5), shorewall-actions(5), shorewall-blacklist(5), shorewall_interfaces(5), shorewall-ipsets(5), shorewall-maclist(5), shorewall-masq(5), shorewall-nat(5), shorewall-nesting(5), shorewall-netmap(5), shorewall-params(5), shorewall-policy(5), shorewall-providers(5), shorewall-proxyarp(5), shorewall-rtrules(5), shorewall-routestopped(5), shorewall-rules(5), shorewall.conf(5), shorewall-secmarks(5), shorewall-tcclasses(5), shorewall-tcdevices(5), shorewall-mangle(5), shorewall-tos(5), shorewall-tunnels(5), shorewall-zones(5)
NOTES
1. shorewall-zones
http://www.shorewall.net/manpages/shorewall-zones.html
2. shorewall-interfaces
http://www.shorewall.net/manpages/shorewall-interfaces.html
3. shorewall-exclusion
http://www.shorewall.net/manpages/shorewall-exclusion.html
4. shorewall-blacklist
http://www.shorewall.net/manpages/shorewall-blacklist.html
5. shorewall-maclist
http://www.shorewall.net/manpages/shorewall-maclist.html
6. shorewall.conf
http://www.shorewall.net/manpages/shorewall.conf.html
7. http://www.shorewall.net/configuration_file_basics.htm#Pairs
http://www.shorewall.net/configuration_file_basics.htm#Pairs
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