Provided by: shorewall6_4.5.21.6-1_all 
NAME
conntrack - shorewall6 conntrack file
SYNOPSIS
/etc/shorewall6/conntrack
DESCRIPTION
The original intent of the notrack file was to exempt certain traffic from Netfilter
connection tracking. Traffic matching entries in the file were not to be tracked.
The role of the file was expanded in Shorewall 4.4.27 to include all rules that can be
added in the Netfilter raw table. In 4.5.7, the file's name was changed to conntrack.
The file supports two different column layouts: FORMAT 1, FORMAT 2, and FORMAT 3, FORMAT 1
being the default. The three differ as follows:
· in FORMAT 2 and 3, there is an additional leading ACTION column.
· in FORMAT 3, the SOURCE column accepts no zone name; rather the ACTION column allows a
SUFFIX that determines the chain(s) that the generated rule will be added to.
When an entry in the following form is encountered, the format of the following entries
are assumed to be of the specified format.
[?]FORMAT
format
where format is either 1,2 or 3.
Format 3 was introduced in Shorewall 4.5.10. The optional '?' was introduced in Shorewall
4.5.11 and ?FORMAT is the preferred form; the form without the '?' is deprecated.
Comments may be attached to Netfilter rules generated from entries in this file through
the use of COMMENT lines. These lines begin with the word COMMENT; the remainder of the
line is treated as a comment which is attached to subsequent rules until another COMMENT
line is found or until the end of the file is reached. To stop adding comments to rules,
use a line with only the word COMMENT.
Note
Beginning with Shorewall 4.5.11, ?COMMENT is a synonym for COMMENT and is preferred.
The columns in the file are as follows (where the column name is followed by a different
name in parentheses, the different name is used in the alternate specification syntax).
ACTION - {NOTRACK|CT:helper:name[(arg=val[,...])|CT:notrack|drop}[:chain-designator]
This column is only present when FORMAT >= 2. Values other than NOTRACK require CT
Targetsupport in your iptables and kernel.
· NOTRACK or CT:notrack
Disables connection tracking for this packet.
· DROP
Added in Shorewall 4.5.10. Silently discard the packet.
· helper:name
Attach the helper identified by the name to this connection. This is more flexible
than loading the conntrack helper with preset ports. May be followed by an option
list of arg=val pairs in parentheses:
· ctevents=event[,...]
Only generate the specified conntrack events for this connection. Possible
event types are: new, related, destroy, reply, assured, protoinfo, helper,
mark (this is connection mark, not packet mark), natseqinfo, and secmark. If
more than one event is listed, the event list must be enclosed in parentheses
(e.g., ctevents=(new,related)).
· expevents=new
Only generate a new expectation events for this connection.
When FORMAT = 1, this column is not present and the rule is processed as if NOTRACK
had been entered in this column.
Beginning with Shorewall 4.5.10, when FORMAT = 3, this column can end with a colon
followed by a chain-designator. The chain-designator can be one of the following:
P
The rule is added to the raw table PREROUTING chain. This is the default if no
chain-designator is present.
O
The rule is added to the raw table OUTPUT chain.
PO or OP
The rule is added to the raw table PREROUTING and OUTPUT chains.
SOURCE (formats 1 and 2) – zone[:interface][:address-list]
where zone is the name of a zone, interface is an interface to that zone, and
address-list is a comma-separated list of addresses (may contain exclusion - see
shorewall6-exclusion[1] (5)).
Beginning with Shorewall 4.5.7, all can be used as the zone name to mean all zones.
Beginning with Shorewall 4.5.10, all- can be used as the zone name to mean all
off-firewall zones.
SOURCE (format 3) – {-|interface[:address-list]|address-list}
Where interface is an interface to that zone, and address-list is a comma-separated
list of addresses (may contain exclusion - see shorewall-exclusion[1] (5)).
COMMENT is only allowed in format 1; the remainder of the line is treated as a comment
that will be associated with the generated rule(s).
DEST – {-|interface[:address-list]|address-list}
where address-list is a comma-separated list of addresses (may contain exclusion - see
shorewall6-exclusion[1] (5)).
PROTO – protocol-name-or-number[,...]
A protocol name from /etc/protocols or a protocol number.
Beginning with Shorewall 4.5.12, this column can accept a comma-separated list of
protocols.
DEST PORT(S) (dport) - port-number/service-name-list
A comma-separated list of port numbers and/or service names from /etc/services. May
also include port ranges of the form low-port:high-port if your kernel and iptables
include port range support.
SOURCE PORT(S) (sport) - port-number/service-name-list
A comma-separated list of port numbers and/or service names from /etc/services. May
also include port ranges of the form low-port:high-port if your kernel and iptables
include port range support.
Beginning with Shorewall 4.5.15, you may place '=' in this column, provided that the
DEST PORT(S) column is non-empty. This causes the rule to match when either the source
port or the destination port in a packet matches one of the ports specified in DEST
PORTS(S).
USER/GROUP (user) – [user][:group]
May only be specified if the SOURCE zone is $FW. Specifies the effective user id and
or group id of the process sending the traffic.
SWITCH - [!]switch-name[={0|1}]
Added in Shorewall6 4.5.10 and allows enabling and disabling the rule without
requiring shorewall6 restart.
Enables the rule if the value stored in /proc/net/nf_condition/switch-name is 1.
Disables the rule if that file contains 0 (the default). If '!' is supplied, the test
is inverted such that the rule is enabled if the file contains 0.
Within the switch-name, '@0' and '@{0}' are replaced by the name of the chain to which
the rule is a added. The switch-name (after '@...' expansion) must begin with a letter
and be composed of letters, decimal digits, underscores or hyphens. Switch names must
be 30 characters or less in length.
Switches are normally off. To turn a switch on:
echo 1 >
/proc/net/nf_condition/switch-name
To turn it off again:
echo 0 >
/proc/net/nf_condition/switch-name
Switch settings are retained over shorewall6 restart.
When the switch-name is followed by =0 or =1, then the switch is initialized to off or
on respectively by the start command. Other commands do not affect the switch setting.
EXAMPLES
Example 1:
Use the FTP helper for TCP port 21 connections from the firewall itself.
FORMAT 2
#ACTION SOURCE DEST PROTO DEST SOURCE USER/GROUP
# PORT(S) PORT(S)
CT:helper:ftp(expevents=new) fw - tcp 21
Example 2 (Shorewall 4.5.10 or later):
Drop traffic to/from all zones to IP address 2001:1.2.3::4
FORMAT 2
#ACTION SOURCE DEST PROTO DEST SOURCE USER/GROUP
# PORT(S) PORT(S)
DROP all-:2001:1.2.3::4 -
DROP all 2001:1.2.3::4
or
FORMAT 3
#ACTION SOURCE DEST PROTO DEST SOURCE USER/GROUP
# PORT(S) PORT(S)
DROP:P 2001:1.2.3::4 -
DROP:PO - 2001:1.2.3::4
FILES
/etc/shorewall6/notrack
SEE ALSO
http://shorewall.net/configuration_file_basics.htm#Pairs
shorewall6(8), shorewall6-accounting(5), shorewall6-actions(5), shorewall6-blacklist(5),
shorewall6-hosts(5), shorewall6-interfaces(5), shorewall6-ipsec(5),
shorewall6-netmap(5),shorewall6-params(5), shorewall6-policy(5), shorewall6-providers(5),
shorewall6-proxyarp(5), shorewall6-rtrules(5), shorewall6-routestopped(5),
shorewall6-rules(5), shorewall6.conf(5), shorewall6-secmarks(5), shorewall6-tcclasses(5),
shorewall6-tcdevices(5), shorewall6-tcrules(5), shorewall6-tos(5), shorewall6-tunnels(5),
shorewall-zones(5)
NOTES
1. shorewall6-exclusion
http://www.shorewall.netshorewall-exclusion.html
[FIXME: source] 01/30/2014 SHOREWALL6-CONNTRAC(5)