SHOREWALL-RULES(5) | [FIXME: manual] | SHOREWALL-RULES(5) |
NAME¶
rules - Shorewall rules fileSYNOPSIS¶
/etc/shorewall/rules
DESCRIPTION¶
Entries in this file govern connection establishment by defining exceptions to the policies layed 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.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 ACCEPT rule inserted at the end of this section.
NEW
Packets in the NEW, INVALID and UNTRACKED
states are processed by rules in this section.
•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
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[6](5) or in /usr/share/shorewall/actions.std then:
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}
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).
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.
NONAT
Excludes the connection from any subsequent
DNAT[-] or REDIRECT[-] rules but doesn't generate a rule to
accept the traffic.
DROP
Ignore the request.
DROP!
like DROP but exempts the rule from being
suppressed by OPTIMIZE=1 in shorewall.conf[2](5).
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.
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).
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.
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.
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.
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[3](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[4](5) for
additional information.
CONTINUE!
like CONTINUE but exempts the rule from being
suppressed by OPTIMIZE=1 in shorewall.conf[2](5).
LOG
Simply log the packet and continue with the
next rule.
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).
NFLOG[(nflog-parameters)]
queues matching packets to a backend logging
daemon via a netlink socket then continues to the next rule. See
http://www.shorewall.net/shorewall_logging.html[5].
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).
COUNT
Simply increment the rule's packet and byte
count and pass the packet to the next rule.
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.
action
The name of an action declared in
shorewall-actions[6](5) or in /usr/share/shorewall/actions.std.
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.
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 tupple 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.
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 tupple 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 deletec 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.
•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.
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[3] (5).
Ths 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 apersand ('&') followed by the logican 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
DEST -
{zone|zone-list[+]|{all|any}[+][
-]}[:{interface|address-or-range[,address-or-range]...[exclusion]|exclusion|+ipset|^countrycode-list}][:port[:random]]
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).
Location of Server. May be a zone declared in
shorewall-zones[3](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[3] (5).
Ths 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:
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)).
Restrictions:
1. MAC addresses are not allowed (this is a Netfilter restriction).
2. You may not specify both an interface and an address.
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 apersand ('&') 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 modifiy the destination port. A destination port may only be included if
the ACTION is DNAT or REDIRECT.
Example:
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}
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.
loc:192.168.1.3:3128 specifies a local
server at IP address 192.168.1.3 and listening on port 3128.
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 numberic 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 listsed.
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
multiport 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.
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
multiport 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 apersand ('&') 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 whitespace
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][
+program-name]
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).
Examples:
joe
MARK - [!]value[/mask][:C]
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
+upnpd
program named upnpd
Important
The ability to specify a program name was removed from Netfilter in kernel
version 2.6.14.
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.
!
CONNLIMIT - [!]limit[:mask]
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.
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[&timelement...]
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]
HEADERS
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.
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
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. switch-name 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:
/proc/net/nf_condition/switch-name
echo 0 >
/proc/net/nf_condition/switch-name
Switch settings are retained over shorewall restart./proc/net/nf_condition/switch-name
EXAMPLES¶
Example 1:Accept SMTP requests from the DMZ to the
internet
Example 2:
#ACTION SOURCE DEST PROTO DEST SOURCE ORIGINAL # PORT PORT(S) DEST ACCEPT dmz net tcp smtp
Forward all ssh and http connection requests
from the internet to local system 192.168.1.3
Example 3:
#ACTION SOURCE DEST PROTO DEST SOURCE ORIGINAL # PORT PORT(S) DEST DNAT net loc:192.168.1.3 tcp ssh,http
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
Example 4:
#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
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
Example 5:
#ACTION SOURCE DEST PROTO DEST SOURCE ORIGINAL # PORT PORT(S) DEST REDIRECT loc 3128 tcp www - !192.168.2.2
All http requests from the internet to address
130.252.100.69 are to be forwarded to 192.168.1.3
Example 6:
#ACTION SOURCE DEST PROTO DEST SOURCE ORIGINAL # PORT PORT(S) DEST DNAT net loc:192.168.1.3 tcp 80 - 130.252.100.69
You want to accept SSH connections to your
firewall only from internet IP addresses 130.252.100.69 and 130.252.100.70
Example 7:
#ACTION SOURCE DEST PROTO DEST SOURCE ORIGINAL # PORT PORT(S) DEST ACCEPT net:130.252.100.69,130.252.100.70 $FW \ tcp 22
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
Example 8:
#ACTION SOURCE DEST PROTO DEST SOURCE ORIGINAL # PORT PORT(S) DEST DNAT net loc:192.168.1.3:22 tcp 2222
You want to redirect connection requests to
port 80 randomly to the port range 81-90.
Example 9:
#ACTION SOURCE DEST PROTO DEST SOURCE ORIGINAL # PORT PORT(S) DEST REDIRECT net $FW::81-90:random tcp www
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[3](8):
shorewall-interfaces[8](8):
shorewall-host[10](8):
rules:
Note that it would have been tempting to simply define the loc zone entirely in
shorewall-interfaces(8):
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:
#ZONE TYPE OPTIONS fw firewall net ipv4 dmz ipv4 loc ipv4
#ZONE INTERFACE BROADCAST OPTIONS net ppp0 loc eth1 detect dmz eth2 detect - ppp+ # Addresses are assigned from 192.168.3.0/24
#ZONE HOST(S) OPTIONS loc ppp+:192.168.3.0/24
#ACTION SOURCE DEST PROTO DEST # PORT(S) REDIRECT loc 3128 tcp 80
#******************* INCORRECT ***************** #ZONE INTERFACE BROADCAST OPTIONS net ppp0 loc eth1 detect loc ppp+ dmz eth2
Add the tupple (source IP, dest port, dest IP)
of an incoming SSH connection to the ipset S:
Example 11:
#ACTION SOURCE DEST PROTO DEST # PORT(S) ADD(+S:dst,src,dst) net fw tcp 22
You wish to limit SSH connections from remote
systems to 1/min with a burst of three (to allow for limited retry):
Example 12:
#ACTION SOURCE DEST PROTO DEST SOURCE ORIGINAL RATE # PORT(S) PORT(S) DEST LIMIT SSH(ACCEPT) net all - - - - s:1/min:3
Forward port 80 to dmz host $BACKUP if switch
'primary_down' is on.
Example 13:
#ACTION SOURCE DEST PROTO DEST SOURCE ORIGINAL RATE USER/ MARK CONNLIMIT TIME HEADERS SWITCH # PORT(S) PORT(S) DEST LIMIT GROUP DNAT net dmz:$BACKUP tcp 80 - - - - - - - - primary_down
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 22
FILES¶
/etc/shorewall/rulesSEE 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), shorweall-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
- 2.
- shorewall.conf
- 3.
- shorewall-zones
- 4.
- shorewall-nesting
- 6.
- shorewall-actions
- 7.
- shorewall-exclusion
- 8.
- shorewall-interfaces
- 10.
- shorewall-host
06/28/2012 | [FIXME: source] |