SHOREWALL6-CONNTRAC(5) [FIXME: manual] SHOREWALL6-CONNTRAC(5)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.net/manpages6/shorewall-exclusion.html
[FIXME: source] 12/19/2013 SHOREWALL6-CONNTRAC(5)
