Provided by: shorewall_4.5.21.6-1_all 
NAME
rules - Shorewall rules file
SYNOPSIS
/etc/shorewall/rules
DESCRIPTION
Entries in this file govern connection establishment by defining exceptions to the
policies laid out in shorewall-policy[1](5). By default, subsequent requests and responses
are automatically allowed using connection tracking. For any particular (source,dest) pair
of zones, the rules are evaluated in the order in which they appear in this file and the
first terminating match is the one that determines the disposition of the request. All
rules are terminating except LOG and COUNT rules.
Warning
If you masquerade or use SNAT from a local system to the internet, you cannot use an
ACCEPT rule to allow traffic from the internet to that system. You must use a DNAT
rule instead.
The rules file is divided into sections. Each section is introduced by a "Section Header"
which is a line beginning with SECTION and followed by the section name.
Sections are as follows and must appear in the order listed:
ALL
This section was added in Shorewall 4.4.23. Rules in this section are applied,
regardless of the connection tracking state of the packet.
ESTABLISHED
Packets in the ESTABLISHED state are processed by rules in this section.
The only ACTIONs allowed in this section are ACCEPT, DROP, REJECT, LOG and QUEUE
There is an implicit ACCEPT rule inserted at the end of this section.
RELATED
Packets in the RELATED state are processed by rules in this section.
The only ACTIONs allowed in this section are ACCEPT, DROP, REJECT, LOG and QUEUE
There is an implicit rule added at the end of this section that invokes the
RELATED_DISPOSITION (shorewall.conf[2](5)).
INVALID
Added in Shorewall 4.5.13. Packets in the INVALID state are processed by rules in this
section.
The only Actions allowed in this section are ACCEPT, DROP, REJECT, LOG and QUEUE.
There is an implicit rule added at the end of this section that invokes the
INVALID_DISPOSITION (shorewall.conf[2](5)).
UNTRACKED
Added in Shorewall 4.5.13. Packets in the UNTRACKED state are processed by rules in
this section.
The only Actions allowed in this section are ACCEPT, DROP, REJECT, LOG and QUEUE.
There is an implicit rule added at the end of this section that invokes the
UNTRACKED_DISPOSITION (shorewall.conf[2](5)).
NEW
Packets in the NEW, INVALID and UNTRACKED states are processed by rules in this
section.
Note
If you are not familiar with Netfilter to the point where you are comfortable with the
differences between the various connection tracking states, then it is suggested that
you omit the ESTABLISHED and RELATED sections and place all of your non-blacklisting
rules in the NEW section (That's after the line that reads SECTION NEW').
Warning
If you specify FASTACCEPT=Yes in shorewall.conf[2](5) then the ALL, ESTABLISHED and
RELATED sections must be empty.
An except is made if you are running Shorewall 4.4.27 or later and you have specified
a non-default value for RELATED_DISPOSITION or RELATED_LOG_LEVEL. In that case, you
may have rules in the RELATED section of this file.
You may omit any section that you don't need. If no Section Headers appear in the file
then all rules are assumed to be in the NEW section.
When defining rules that rewrite the destination IP address and/or port number (namely
DNAT and REDIRECT rules), it is important to keep straight which columns in the file
specify the packet before rewriting and which specify how the packet will look after
rewriting.
• The DEST column specifies the final destination for the packet after rewriting and can
include the final IP address and/or port number.
• The remaining columns specify characteristics of the packet before rewriting. In
particular, the ORIGINAL DEST column gives the original destination IP address of the
packet and the DEST PORT(S) column give the original destination port(s).
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 - target[:{log-level|none}[!][:tag]]
Specifies the action to be taken if the connection request matches the rule. target
must be one of the following.
ACCEPT
Allow the connection request.
ACCEPT+
like ACCEPT but also excludes the connection from any subsequent matching DNAT[-]
or REDIRECT[-] rules.
ACCEPT!
like ACCEPT but exempts the rule from being suppressed by OPTIMIZE=1 in
shorewall.conf[2](5).
action
The name of an action declared in shorewall-actions[3](5) or in
/usr/share/shorewall/actions.std.
ADD(ipset:flags)
Added in Shorewall 4.4.12. Causes addresses and/or port numbers to be added to the
named ipset. The flags specify the address or tuple to be added to the set and
must match the type of ipset involved. For example, for an iphash ipset, either
the SOURCE or DESTINATION address can be added using flags src or dst respectively
(see the -A command in ipset (8)).
ADD is non-terminating. Even if a packet matches the rule, it is passed on to the
next rule.
AUDIT[(accept|drop|reject)]
Added in Shorewall 4.5.10. Audits the packet with the specified type; if the type
is omitted, then drop is assumed. Require AUDIT_TARGET support in the kernel and
iptables.
A_ACCEPT, A_ACCEPT+ and A_ACCEPT!
Added in Shorewall 4.4.20. Audited versions of ACCEPT, ACCEPT+ and ACCEPT!
respectively. Require AUDIT_TARGET support in the kernel and iptables.
A_DROP and A_DROP!
Added in Shorewall 4.4.20. Audited versions of DROP and DROP! respectively.
Require AUDIT_TARGET support in the kernel and iptables.
A_REJECT AND A_REJECT!
Added in Shorewall 4.4.20. Audited versions of REJECT and REJECT! respectively.
Require AUDIT_TARGET support in the kernel and iptables.
[?]COMMENT
the rest of the line will be attached as a comment to the Netfilter rule(s)
generated by the following entries. The comment will appear delimited by "/* ...
*/" in the output of "shorewall show <chain>". To stop the comment from being
attached to further rules, simply include COMMENT on a line by itself.
Note
Beginning with Shorewall 4.5.11, ?COMMENT is a synonym for COMMENT and is
preferred.
CONTINUE
For experts only.
Do not process any of the following rules for this (source zone,destination zone).
If the source and/or destination IP address falls into a zone defined later in
shorewall-zones[4](5) or in a parent zone of the source or destination zones, then
this connection request will be passed to the rules defined for that (those)
zone(s). See shorewall-nesting[5](5) for additional information.
CONTINUE!
like CONTINUE but exempts the rule from being suppressed by OPTIMIZE=1 in
shorewall.conf[2](5).
COUNT
Simply increment the rule's packet and byte count and pass the packet to the next
rule.
DEL(ipset:flags)
Added in Shorewall 4.4.12. Causes an entry to be deleted from the named ipset. The
flags specify the address or tuple to be deleted from the set and must match the
type of ipset involved. For example, for an iphash ipset, either the SOURCE or
DESTINATION address can be deleted using flags src or dst respectively (see the -D
command in ipset (8)).
DEL is non-terminating. Even if a packet matches the rule, it is passed on to the
next rule.
DNAT
Forward the request to another system (and optionally another port).
DNAT-
Advanced users only.
Like DNAT but only generates the DNAT iptables rule and not the companion ACCEPT
rule.
DROP
Ignore the request.
DROP!
like DROP but exempts the rule from being suppressed by OPTIMIZE=1 in
shorewall.conf[2](5).
HELPER
Added in Shorewall 4.5.7. This action requires that the HELPER column contains the
name of the Netfilter helper to be associated with connections matching this
connection. May only be specified in the NEW section and is useful for being able
to specify a helper when the applicable policy is ACCEPT. No destination zone
should be specified in HELPER rules.
INLINE[(action)]
Added in Shorewall 4.5.16. This action allows you to construct most of the rule
yourself using iptables syntax. The part that you specify must follow a semicolon
(';') and is completely free-form. If the target of the rule (the part following
'j') is something that Shorewall supports in the ACTION column, then you may
enclose it in parentheses (e.g., INLINE(ACCEPT)). Otherwise, you can include it
after the semicolon. In this case, you must declare the target as a builtin action
in shorewall-actions[3](5).
Some considerations when using INLINE:
• The p, s, d, i, o, policy, and state match (state or conntrack --ctstate)
matches will always appear in the front of the rule in that order.
• When multiple matches are specified, the compiler will keep them in the order
in which they appear (excluding the above listed ones), but they will not
necessarily be at the end of the generated rule. For example, if addresses are
specified in the SOURCE and/or DEST columns, their generated matches will
appear after those specified using ';'.
LOG:level
Simply log the packet and continue with the next rule.
macro[(macrotarget)]
The name of a macro defined in a file named macro.macro. If the macro accepts an
action parameter (Look at the macro source to see if it has PARAM in the TARGET
column) then the macro name is followed by the parenthesized macrotarget (ACCEPT,
DROP, REJECT, ...) to be substituted for the parameter.
Example: FTP(ACCEPT).
The older syntax where the macro name and the target are separated by a slash
(e.g. FTP/ACCEPT) is still allowed but is deprecated.
NFLOG[(nflog-parameters)]
Added in Shorewall 4.5.9.3. Queues matching packets to a back end logging daemon
via a netlink socket then continues to the next rule. See
http://www.shorewall.net/shorewall_logging.html[6].
Similar to LOG:NFLOG[(nflog-parameters)], except that the log level is not changed
when this ACTION is used in an action or macro body and the invocation of that
action or macro specifies a log level.
NFQUEUE[(queuenumber)]
Queues the packet to a user-space application using the nfnetlink_queue mechanism.
If a queuenumber is not specified, queue zero (0) is assumed.
NFQUEUE![(queuenumber)]
like NFQUEUE but exempts the rule from being suppressed by OPTIMIZE=1 in
shorewall.conf[2](5).
NONAT
Excludes the connection from any subsequent DNAT[-] or REDIRECT[-] rules but
doesn't generate a rule to accept the traffic.
QUEUE
Queue the packet to a user-space application such as ftwall
(http://p2pwall.sf.net). The application may reinsert the packet for further
processing.
QUEUE!
like QUEUE but exempts the rule from being suppressed by OPTIMIZE=1 in
shorewall.conf[2](5).
REJECT
disallow the request and return an icmp-unreachable or an RST packet.
REJECT!
like REJECT but exempts the rule from being suppressed by OPTIMIZE=1 in
shorewall.conf[2](5).
REDIRECT
Redirect the request to a server running on the firewall.
REDIRECT-
Advanced users only.
Like REDIRECT but only generates the REDIRECT iptables rule and not the companion
ACCEPT rule.
ULOG[(ulog-parameters)]
Added in Shorewall 4.5.10. Queues matching packets to a back end logging daemon
via a netlink socket then continues to the next rule. See
http://www.shorewall.net/shorewall_logging.html[6].
Similar to LOG:ULOG[(ulog-parameters)], except that the log level is not changed
when this ACTION is used in an action or macro body and the invocation of that
action or macro specifies a log level.
The target may optionally be followed by ":" and a syslog log level (e.g, REJECT:info
or Web(ACCEPT):debug). This causes the packet to be logged at the specified level.
Note that if the ACTION involves destination network address translation (DNAT,
REDIRECT, etc.) then the packet is logged before the destination address is rewritten.
If the ACTION names an action declared in shorewall-actions[3](5) or in
/usr/share/shorewall/actions.std then:
• If the log level is followed by "!' then all rules in the action are logged at the
log level.
• If the log level is not followed by "!" then only those rules in the action that
do not specify logging are logged at the specified level.
• The special log level none! suppresses logging by the action.
You may also specify ULOG or NFLOG (must be in upper case) as a log level.This will
log to the ULOG or NFLOG target for routing to a separate log through use of ulogd
(http://www.netfilter.org/projects/ulogd/index.html).
Actions specifying logging may be followed by a log tag (a string of alphanumeric
characters) which is appended to the string generated by the LOGPREFIX (in
shorewall.conf[2](5)).
Example: ACCEPT:info:ftp would include 'ftp ' at the end of the log prefix generated
by the LOGPREFIX setting.
SOURCE -
{zone|zone-list[+]|{all|any}[+][-]}[:interface][:{address-or-range[,address-or-range]...[exclusion]|exclusion|+ipset|^countrycode-list}
Source hosts to which the rule applies. May be a zone declared in
/etc/shorewall/zones, $FW to indicate the firewall itself, all, all+, all-, all+- or
none.
Beginning with Shorewall 4.4.13, you may use a zone-list which consists of a
comma-separated list of zones declared in shorewall-zones[4] (5). This zone-list may
be optionally followed by "+" to indicate that the rule is to apply to intra-zone
traffic as well as inter-zone traffic.
When none is used either in the SOURCE or DEST column, the rule is ignored.
all means "All Zones", including the firewall itself. all- means "All Zones, except
the firewall itself". When all[-] is used either in the SOURCE or DEST column
intra-zone traffic is not affected. When all+[-] is "used, intra-zone traffic is
affected. Beginning with Shorewall 4.4.13, exclusion is supported -- see see
shorewall-exclusion[7](5).
Except when all[+][-] or any[+][-] is specified, clients may be further restricted to
a list of networks and/or hosts by appending ":" and a comma-separated list of network
and/or host addresses. Hosts may be specified by IP or MAC address; mac addresses must
begin with "~" and must use "-" as a separator.
The above restriction on all[+][-] and any[+][-] is removed in Shorewall-4.4.13.
any is equivalent to all when there are no nested zones. When there are nested zones,
any only refers to top-level zones (those with no parent zones). Note that any
excludes all vserver zones, since those zones are nested within the firewall zone.
Hosts may also be specified as an IP address range using the syntax
lowaddress-highaddress. This requires that your kernel and iptables contain iprange
match support. If your kernel and iptables have ipset match support then you may give
the name of an ipset prefaced by "+". The ipset name may be optionally followed by a
number from 1 to 6 enclosed in square brackets ([]) to indicate the number of levels
of source bindings to be matched.
Beginning with Shorewall 4.4.17, the primary IP address of a firewall interface can be
specified by an ampersand ('&') followed by the logical name of the interface as found
in the INTERFACE column of shorewall-interfaces[8] (5).
Beginning with Shorewall 4.5.4, A countrycode-list may be specified. A
countrycode-list is a comma-separated list of up to 15 two-character ISO-3661 country
codes enclosed in square brackets ('[...]') and preceded by a caret ('^'). When a
single country code is given, the square brackets may be omitted. A list of country
codes supported by Shorewall may be found at http://www.shorewall.net/ISO-3661.html.
Specifying a countrycode-list requires GeoIP Match support in your iptables and
Kernel.
You may exclude certain hosts from the set already defined through use of an exclusion
(see shorewall-exclusion[7](5)).
Examples:
dmz:192.168.2.2
Host 192.168.2.2 in the DMZ
net:155.186.235.0/24
Subnet 155.186.235.0/24 on the Internet
loc:192.168.1.1,192.168.1.2
Hosts 192.168.1.1 and 192.168.1.2 in the local zone.
loc:~00-A0-C9-15-39-78
Host in the local zone with MAC address 00:A0:C9:15:39:78.
net:192.0.2.11-192.0.2.17
Hosts 192.0.2.11-192.0.2.17 in the net zone.
net:!192.0.2.11-192.0.2.17
All hosts in the net zone except for 192.0.2.11-192.0.2.17.
net:155.186.235.0/24!155.186.235.16/28
Subnet 155.186.235.0/24 on the Internet except for 155.186.235.16/28
$FW:ð0
The primary IP address of eth0 in the firewall zone (Shorewall 4.4.17 and later).
DEST -
{zone|zone-list[+]|{all|any}[+][-]}[:{interface|address-or-range[,address-or-range]...[exclusion]|exclusion|+ipset|^countrycode-list}][:port[:random]]
Location of Server. May be a zone declared in shorewall-zones[4](5), $FW to indicate
the firewall itself, all. all+ or none.
Beginning with Shorewall 4.4.13, you may use a zone-list which consists of a
comma-separated list of zones declared in shorewall-zones[4] (5). This zone-list may
be optionally followed by "+" to indicate that the rule is to apply to intra-zone
traffic as well as inter-zone traffic.
Beginning with Shorewall 4.5.4, A countrycode-list may be specified. A
countrycode-list is a comma-separated list of up to 15 two-character ISO-3661 country
codes enclosed in square brackets ('[...]') and preceded by a caret ('^'). When a
single country code is given, the square brackets may be omitted. A list of country
codes supported by Shorewall may be found at http://www.shorewall.net/ISO-3661.html.
Specifying a countrycode-list requires GeoIP Match support in your iptables and
Kernel.
When none is used either in the SOURCE or DEST column, the rule is ignored.
When all is used either in the SOURCE or DEST column intra-zone traffic is not
affected. When all+ is used, intra-zone traffic is affected. Beginning with Shorewall
4.4.13, exclusion is supported -- see see shorewall-exclusion[7](5).
any is equivalent to all when there are no nested zones. When there are nested zones,
any only refers to top-level zones (those with no parent zones).
The zone should be omitted in DNAT-, REDIRECT- and NONAT rules.
If the DEST zone is a bport zone, then either:
1. the SOURCE must be all[+][-], or
2. the SOURCE zone must be another bport zone associated with the same bridge, or
3. the SOURCE zone must be an ipv4 zone that is associated with only the same bridge.
Except when all[+]|[-] is specified, the server may be further restricted to a
particular network, host or interface by appending ":" and the network, host or
interface. See SOURCE above.
You may exclude certain hosts from the set already defined through use of an exclusion
(see shorewall-exclusion[7](5)).
Restriction: MAC addresses are not allowed (this is a Netfilter restriction).
Like in the SOURCE column, you may specify a range of IP addresses using the syntax
lowaddress-highaddress. When the ACTION is DNAT or DNAT-, the connections will be
assigned to addresses in the range in a round-robin fashion.
If you kernel and iptables have ipset match support then you may give the name of an
ipset prefaced by "+". The ipset name may be optionally followed by a number from 1 to
6 enclosed in square brackets ([]) to indicate the number of levels of destination
bindings to be matched. Only one of the SOURCE and DEST columns may specify an ipset
name.
Beginning with Shorewall 4.4.17, the primary IP address of a firewall interface can be
specified by an ampersand ('&') followed by the logical name of the interface as found
in the INTERFACE column of shorewall-interfaces[8] (5).
The port that the server is listening on may be included and separated from the
server's IP address by ":". If omitted, the firewall will not modify the destination
port. A destination port may only be included if the ACTION is DNAT or REDIRECT.
Example:
loc:192.168.1.3:3128 specifies a local server at IP address 192.168.1.3 and
listening on port 3128.
The port may be specified as a service name. You may specify a port range in the form
lowport-highport to cause connections to be assigned to ports in the range in
round-robin fashion. When a port range is specified, lowport and highport must be
given as integers; service names are not permitted. Additionally, the port range may
be optionally followed by :random which causes assignment to ports in the list to be
random.
If the ACTION is REDIRECT or REDIRECT-, this column needs only to contain the port
number on the firewall that the request should be redirected to. That is equivalent to
specifying $FW::port.
PROTO- {-|tcp:syn|ipp2p|ipp2p:udp|ipp2p:all|protocol-number|protocol-name|all}
Optional Protocol - ipp2p* requires ipp2p match support in your kernel and iptables.
tcp:syn implies tcp plus the SYN flag must be set and the RST,ACK and FIN flags must
be reset.
Beginning with Shorewall 4.4.19, this column can contain a comma-separated list of
protocol-numbers and/or protocol names.
DEST PORT(S) (dport) - {-|port-name-number-or-range[,port-name-number-or-range]...}
Optional destination Ports. A comma-separated list of Port names (from services(5)),
port numbers or port ranges; if the protocol is icmp, this column is interpreted as
the destination icmp-type(s). ICMP types may be specified as a numeric type, a numeric
type and code separated by a slash (e.g., 3/4), or a typename. See
http://www.shorewall.net/configuration_file_basics.htm#ICMP. Note that prior to
Shorewall 4.4.19, only a single ICMP type may be listed.
If the protocol is ipp2p, this column is interpreted as an ipp2p option without the
leading "--" (example bit for bit-torrent). If no port is given, ipp2p is assumed.
A port range is expressed as lowport:highport.
This column is ignored if PROTO = all but must be entered if any of the following
columns are supplied. In that case, it is suggested that this field contain a dash
(-).
If your kernel contains multi-port match support, then only a single Netfilter rule
will be generated if in this list and the CLIENT PORT(S) list below:
1. There are 15 or less ports listed.
2. No port ranges are included or your kernel and iptables contain extended multi-port
match support.
SOURCE PORT(S) (sport) - {-|port-name-number-or-range[,port-name-number-or-range]...}
Optional port(s) used by the client. If omitted, any source port is acceptable.
Specified as a comma- separated list of port names, port numbers or port ranges.
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). Use of '=' requires multi-port match in your iptables and kernel.
Warning
Unless you really understand IP, you should leave this column empty or place a
dash (-) in the column. Most people who try to use this column get it wrong.
If you don't want to restrict client ports but need to specify an ORIGINAL DEST in the
next column, then place "-" in this column.
If your kernel contains multi-port match support, then only a single Netfilter rule
will be generated if in this list and the DEST PORT(S) list above:
1. There are 15 or less ports listed.
2. No port ranges are included or your kernel and iptables contain extended multi-port
match support.
ORIGINAL DEST (origdest) - [-|address[,address]...[exclusion]|exclusion]
Optional. If ACTION is DNAT[-] or REDIRECT[-] then if this column is included and is
different from the IP address given in the DEST column, then connections destined for
that address will be forwarded to the IP and port specified in the DEST column.
A comma-separated list of addresses may also be used. This is most useful with the
REDIRECT target where you want to redirect traffic destined for particular set of
hosts. Finally, if the list of addresses begins with "!" (exclusion) then the rule
will be followed only if the original destination address in the connection request
does not match any of the addresses listed.
Beginning with Shorewall 4.4.17, the primary IP address of a firewall interface can be
specified by an ampersand ('&') followed by the logical name of the interface as found
in the INTERFACE column of shorewall-interfaces[8] (5).
For other actions, this column may be included and may contain one or more addresses
(host or network) separated by commas. Address ranges are not allowed. When this
column is supplied, rules are generated that require that the original destination
address matches one of the listed addresses. This feature is most useful when you want
to generate a filter rule that corresponds to a DNAT- or REDIRECT- rule. In this
usage, the list of addresses should not begin with "!".
It is also possible to specify a set of addresses then exclude part of those
addresses. For example, 192.168.1.0/24!192.168.1.16/28 specifies the addresses
192.168.1.0-182.168.1.15 and 192.168.1.32-192.168.1.255. See
shorewall-exclusion[7](5).
See http://shorewall.net/PortKnocking.html[9] for an example of using an entry in this
column with a user-defined action rule.
RATE LIMIT (rate) - [-|[{s|d}:[[name]:]]]rate/{sec|min|hour|day}[:burst]
You may optionally rate-limit the rule by placing a value in this column:
rate is the number of connections per interval (sec or min) and burst is the largest
burst permitted. If no burst is given, a value of 5 is assumed. There may be no no
white-space embedded in the specification.
Example: 10/sec:20
When s: or d: is specified, the rate applies per source IP address or per destination
IP address respectively. The name may be chosen by the user and specifies a hash table
to be used to count matching connections. If not given, the name shorewallN (where N
is a unique integer) is assumed. Where more than one rule specifies the same name, the
connections counts for the rules are aggregated and the individual rates apply to the
aggregated count.
Example: s:ssh:3/min:5
USER/GROUP (user) - [!][user-name-or-number][:group-name-or-number][,...]
This optional column may only be non-empty if the SOURCE is the firewall itself.
When this column is non-empty, the rule applies only if the program generating the
output is running under the effective user and/or group specified (or is NOT running
under that id if "!" is given).
Beginning with Shorewall 4.5.8, multiple user or group names/ids separated by commas
may be specified.
Examples:
joe
program must be run by joe
:kids
program must be run by a member of the 'kids' group
!:kids
program must not be run by a member of the 'kids' group
2001-2099
UIDs 2001 through 2099 (Shorewall 4.5.6 and later)
MARK - [!]value[/mask][:C]
Defines a test on the existing packet or connection mark. The rule will match only if
the test returns true.
If you don't want to define a test but need to specify anything in the following
columns, place a "-" in this field.
!
Inverts the test (not equal)
value
Value of the packet or connection mark.
mask
A mask to be applied to the mark before testing.
:C
Designates a connection mark. If omitted, the packet mark's value is tested.
CONNLIMIT - [!]limit[:mask]
May be used to limit the number of simultaneous connections from each individual host
to limit connections. Requires connlimit match in your kernel and iptables. While the
limit is only checked on rules specifying CONNLIMIT, the number of current connections
is calculated over all current connections from the SOURCE host. By default, the limit
is applied to each host but can be made to apply to networks of hosts by specifying a
mask. The mask specifies the width of a VLSM mask to be applied to the source address;
the number of current connections is then taken over all hosts in the subnet
source-address/mask. When ! is specified, the rule matches when the number of
connection exceeds the limit.
TIME - timeelement[&timeelement...]
May be used to limit the rule to a particular time period each day, to particular days
of the week or month, or to a range defined by dates and times. Requires time match
support in your kernel and iptables.
timeelement may be:
timestart=hh:mm[:ss]
Defines the starting time of day.
timestop=hh:mm[:ss]
Defines the ending time of day.
utc
Times are expressed in Greenwich Mean Time.
localtz
Deprecated by the Netfilter team in favor of kerneltz. Times are expressed in
Local Civil Time (default).
kerneltz
Added in Shorewall 4.5.2. Times are expressed in Local Kernel Time (requires
iptables 1.4.12 or later).
weekdays=ddd[,ddd]...
where ddd is one of Mon, Tue, Wed, Thu, Fri, Sat or Sun
monthdays=dd[,dd],...
where dd is an ordinal day of the month
datestart=yyyy[-mm[-dd[Thh[:mm[:ss]]]]]
Defines the starting date and time.
datestop=yyyy[-mm[-dd[Thh[:mm[:ss]]]]]
Defines the ending date and time.
HEADERS
Added in Shorewall 4.4.15. Not used in IPv4 configurations. If you with to supply a
value for one of the later columns, enter '-' in this column.
SWITCH - [!]switch-name[={0|1}]
Added in Shorewall 4.4.24 and allows enabling and disabling the rule without requiring
shorewall restart.
The rule is enabled if the value stored in /proc/net/nf_condition/switch-name is 1.
The rule is disabled 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 shorewall restart.
Beginning with Shorewall 4.5.10, 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.
HELPER - [helper]
Added in Shorewall 4.5.7.
In the NEW section, causes the named conntrack helper to be associated with this
connection; the contents of this column are ignored unless ACTION is ACCEPT*, DNAT* or
REDIRECT*.
In the RELATED section, will only match if the related connection has the named helper
associated with it.
The helper may be one of:
amanda
ftp
irc
netbios-ns
pptp
Q.931
RAS
sane
sip
snmp
tftp
If the HELPERS option is specified in shorewall.conf[2](5), then any module specified
in this column must be listed in the HELPERS setting.
EXAMPLES
Example 1:
Accept SMTP requests from the DMZ to the internet
#ACTION SOURCE DEST PROTO DEST SOURCE ORIGINAL
# PORT PORT(S) DEST
ACCEPT dmz net tcp smtp
Example 2:
Forward all ssh and http connection requests from the internet to local system
192.168.1.3
#ACTION SOURCE DEST PROTO DEST SOURCE ORIGINAL
# PORT PORT(S) DEST
DNAT net loc:192.168.1.3 tcp ssh,http
Example 3:
Forward all http connection requests from the internet to local system 192.168.1.3
with a limit of 3 per second and a maximum burst of 10
#ACTION SOURCE DEST PROTO DEST SOURCE ORIGINAL RATE
# PORT PORT(S) DEST LIMIT
DNAT net loc:192.168.1.3 tcp http - - 3/sec:10
Example 4:
Redirect all locally-originating www connection requests to port 3128 on the firewall
(Squid running on the firewall system) except when the destination address is
192.168.2.2
#ACTION SOURCE DEST PROTO DEST SOURCE ORIGINAL
# PORT PORT(S) DEST
REDIRECT loc 3128 tcp www - !192.168.2.2
Example 5:
All http requests from the internet to address 130.252.100.69 are to be forwarded to
192.168.1.3
#ACTION SOURCE DEST PROTO DEST SOURCE ORIGINAL
# PORT PORT(S) DEST
DNAT net loc:192.168.1.3 tcp 80 - 130.252.100.69
Example 6:
You want to accept SSH connections to your firewall only from internet IP addresses
130.252.100.69 and 130.252.100.70
#ACTION SOURCE DEST PROTO DEST SOURCE ORIGINAL
# PORT PORT(S) DEST
ACCEPT net:130.252.100.69,130.252.100.70 $FW \
tcp 22
Example 7:
You wish to accept connections from the internet to your firewall on port 2222 and you
want to forward them to local system 192.168.1.3, port 22
#ACTION SOURCE DEST PROTO DEST SOURCE ORIGINAL
# PORT PORT(S) DEST
DNAT net loc:192.168.1.3:22 tcp 2222
Example 8:
You want to redirect connection requests to port 80 randomly to the port range 81-90.
#ACTION SOURCE DEST PROTO DEST SOURCE ORIGINAL
# PORT PORT(S) DEST
REDIRECT net $FW::81-90:random tcp www
Example 9:
Shorewall does not impose as much structure on the Netfilter rules in the 'nat' table
as it does on those in the filter table. As a consequence, when using Shorewall
versions before 4.1.4, care must be exercised when using DNAT and REDIRECT rules with
zones defined with wildcard interfaces (those ending with '+'. Here is an example:
shorewall-zones[4](8):
#ZONE TYPE OPTIONS
fw firewall
net ipv4
dmz ipv4
loc ipv4
shorewall-interfaces[8](8):
#ZONE INTERFACE BROADCAST OPTIONS
net ppp0
loc eth1 detect
dmz eth2 detect
- ppp+ # Addresses are assigned from 192.168.3.0/24
shorewall-host[10](8):
#ZONE HOST(S) OPTIONS
loc ppp+:192.168.3.0/24
rules:
#ACTION SOURCE DEST PROTO DEST
# PORT(S)
REDIRECT loc 3128 tcp 80
Note that it would have been tempting to simply define the loc zone entirely in
shorewall-interfaces(8):
#******************* INCORRECT *****************
#ZONE INTERFACE BROADCAST OPTIONS
net ppp0
loc eth1 detect
loc ppp+
dmz eth2
This would have made it impossible to run a internet-accessible web server in the DMZ
because all traffic entering ppp+ interfaces would have been redirected to port 3128
on the firewall and there would have been no net->fw ACCEPT rule for that traffic.
Example 10:
Add the tuple (source IP, dest port, dest IP) of an incoming SSH connection to the
ipset S:
#ACTION SOURCE DEST PROTO DEST
# PORT(S)
ADD(+S:dst,src,dst) net fw tcp 22
Example 11:
You wish to limit SSH connections from remote systems to 1/min with a burst of three
(to allow for limited retry):
#ACTION SOURCE DEST PROTO DEST SOURCE ORIGINAL RATE
# PORT(S) PORT(S) DEST LIMIT
SSH(ACCEPT) net all - - - - s:1/min:3
Example 12:
Forward port 80 to dmz host $BACKUP if switch 'primary_down' is on.
#ACTION SOURCE DEST PROTO DEST SOURCE ORIGINAL RATE USER/ MARK CONNLIMIT TIME HEADERS SWITCH
# PORT(S) PORT(S) DEST LIMIT GROUP
DNAT net dmz:$BACKUP tcp 80 - - - - - - - - primary_down
Example 13:
Drop all email from the Anonymous Proxy and Satellite Provider address ranges:
#ACTION SOURCE DEST PROTO DEST
# PORT(S)
DROP net:^A1,A2 fw tcp 25
Example 14:
You want to generate your own rule involving iptables targets and matches not
supported by Shorewall.
#ACTION SOURCE DEST PROTO DEST
# PORT(S)
INLINE $FW net ; -p 6 -m mickey-mouse --name test -m set --match-set set1 src -m mickey-mouse --name test2 -j SECCTX --name test3
The above will generate the following iptables-restore input:
-A fw2net -p 6 -m mickey-mouse --name test -m set --match-set set1 src -m mickey-mouse --name test2 -j SECCTX --name test3
Note that SECCTX must be defined as a builtin action in shorewall-actions[3](5):
#ACTION OPTIONS
SECCTX builtin
FILES
/etc/shorewall/rules
SEE ALSO
http://www.shorewall.net/ipsets.html
http://www.shorewall.net/configuration_file_basics.htm#Pairs[11]
http://www.shorewall.net/shorewall_logging.html
shorewall(8), shorewall-accounting(5), shorewall-actions(5), shorewall-blacklist(5),
shorewall-blrules(5), shorewall-hosts(5), shorewall_interfaces(5), shorewall-ipsets(5),
shorewall-maclist(5), shorewall-masq(5), shorewall-nat(5), shorewall-netmap(5),
shorewall-params(5), shorewall-policy(5), shorewall-providers(5), shorewall-proxyarp(5),
shorewall-rtrules(5), shorewall-routestopped(5), shorewall.conf(5), shorewall-secmarks(5),
shorewall-tcclasses(5), shorewall-tcdevices(5), shorewall-tcrules(5), shorewall-tos(5),
shorewall-tunnels(5), shorewall-zones(5)
NOTES
1. shorewall-policy
http://www.shorewall.netshorewall-policy.html
2. shorewall.conf
http://www.shorewall.netshorewall.conf.html
3. shorewall-actions
http://www.shorewall.netshorewall-actions.html
4. shorewall-zones
http://www.shorewall.netshorewall-zones.html
5. shorewall-nesting
http://www.shorewall.netshorewall-nesting.html
6. http://www.shorewall.net/shorewall_logging.html
http://www.shorewall.net/shorewall.logging.html
7. shorewall-exclusion
http://www.shorewall.netshorewall-exclusion.html
8. shorewall-interfaces
http://www.shorewall.netshorewall-interfaces.html
9. http://shorewall.net/PortKnocking.html
http://www.shorewall.net../PortKnocking.html
10. shorewall-host
http://www.shorewall.netshorewall-hosts.html
11. http://www.shorewall.net/configuration_file_basics.htm#Pairs
http://shorewall.net/configuration_file_basics.htm#Pairs
[FIXME: source] 01/30/2014 SHOREWALL-RULES(5)