shorewall6-rules(5)

NAME

rules - Shorewall6 rules file

SYNOPSIS

/etc/shorewall6/rules

DESCRIPTION

Entries in this file govern connection establishment by defining
exceptions to the policies layed out in shorewall6-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 QUEUE rules.

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:

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.
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 rules in the NEW section (That's after the line that reads SECTION NEW').
Warning
If you specify FASTACCEPT=Yes in shorewall6.conf[2](5) then the ESTABLISHED and RELATED sections must be empty.
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.
The columns in the file are as follows.
ACTION {ACCEPT[+|!]|DROP[!]|REJECT[!]|DNAT[-]|SAME[-]|CONTINUE[!]|LOG|QUEUE[!]|NFQUEUE[(queuenumber)]|COMMENT|action|macro[(target)]}[:{log-level|none}[!][:tag]]: Specifies the action to be taken if the connection request matches the rule. Must be one of the following.; ACCEPT
Allow the connection request.; ACCEPT!
like ACCEPT but exempts the rule from being suppressed by
OPTIMIZE=1 in shorewall6.conf[2](5).; DROP
Ignore the request.; DROP!
like DROP but exempts the rule from being suppressed by
OPTIMIZE=1 in shorewall6.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 shorewall6.conf[2](5).; 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
shorewall6-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
shorewall6-nesting[4](5) for additional information.; CONTINUE!
like CONTINUE but exempts the rule from being suppressed by
OPTIMIZE=1 in shorewall6.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 shorewall6.conf[2](5).; NFQUEUE
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!
like NFQUEUE but exempts the rule from being suppressed by
OPTIMIZE=1 in shorewall6.conf[2](5).; 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
"shorewall6 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 shorewall6-actions[5](5) or in /usr/share/shorewall6/actions.std.; macro
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 target (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.; The ACTION may optionally be followed by ":" and a syslog log level (e.g, REJECT:info or ACCEPT:debug). This causes the packet to be
logged at the specified level.; If the ACTION names an action declared in shorewall6-actions[5](5) or in /usr/share/shorewall6/actions.std then:; o If the log level is followed by "!' then all rules in the
action are logged at the log level.; o 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.; o The special log level none! suppresses logging by the action.

You may also specify NFLOG (must be in upper case) as a log level.This will log to the 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 shorewall6.conf[2](5)).

Example: ACCEPT:info:ftp would include 'ftp ' at the end of the log prefix generated by the LOGPREFIX setting.
SOURCE {zone|all[+][-]}[:interface][:<{address-or-range[,address-or-range]...[exclusion]>|exclusion|+ipset}: Source hosts to which the rule applies. May be a zone declared in
/etc/shorewall6/zones, $FW to indicate the firewall itself, all, all+, all-, all+- or none.; 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.; Except when all[+][-] 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.; Hosts may also be specified as an IP address range using the syntax lowaddress-highaddress. This requires that your kernel and ip6tables contain iprange match support. If your kernel and
ip6tables 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.; When an interface is not specified, you may omit the angled brackets ('<' and '>') around the address(es) or you may supply
them to improve readability.; You may exclude certain hosts from the set already defined through use of an exclusion (see shorewall6-exclusion[6](5)).; Examples:; dmz:2002:ce7c::92b4:1::2
Host 2002:ce7c:92b4:1::2 in the DMZ; net:2001:4d48:ad51:24::/64
Subnet 2001:4d48:ad51:24::/64 on the Internet; loc:<2002:cec792b4:1::2,2002:cec792b4:1::44>
Hosts 2002:cec792b4:1::2 and 2002:cec792b4:1::44 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:2001:4d48:ad51:24::/64!2001:4d48:ad51:24:6:/80!2001:4d48:ad51:24:6:/80
Subnet 2001:4d48:ad51:24::/64 on the Internet except for
2001:4d48:ad51:24:6:/80.; Alternatively, clients may be specified by interface by appending
":" to the zone name followed by the interface name. For example,
loc:eth1 specifies a client that communicates with the firewall system through eth1. This may be optionally followed by another
colon (":") and an IP/MAC/subnet address as described above (e.g., loc:eth1:<2002:ce7c::92b4:1::2>). Examples:; loc:eth1:<2002:cec792b4:1::2,2002:cec792b4:1::44>
Hosts 2002:cec792b4:1::2 and 2002:cec792b4:1::44 in the Local
zone, with both originating from eth1
DEST {zone|all[+][-]}[:interface][:<{address-or-range[,address-or-range]...[exclusion]>|exclusion|+ipset}: Location of Server. May be a zone declared in
shorewall6-zones[3](5), $FW to indicate the firewall itself, all. all+ or none.; 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.; 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 shorewall6-exclusion[6](5)).

Restrictions:

1. MAC addresses are not allowed (this is a Netfilter
restriction).

If you kernel and ip6tables 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.
PROTO (Optional) {-|tcp:syn|ipp2p|ipp2p:udp|ipp2p:all|protocol-number|protocol-name|all} Protocol - ipp2p* requires ipp2p match support in your kernel and ip6tables. tcp:syn implies tcp plus the SYN flag must be set and the RST,ACK and FIN flags must be reset.
DEST PORT(S) (Optional) {-|port-name-number-or-range[,port-name-number-or-range]...} 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).
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 ip6tables contain extended multiport match support.
SOURCE PORT(S) (Optional) {-|port-name-number-or-range[,port-name-number-or-range]...} 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 a later 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 ip6tables contain extended multiport match support.
ORIGINAL DEST (Optional) - [-]
Included for compatibility with Shorewall. Enter '-' in this column if you need to specify one of the later columns.
RATE LIMIT (Optional) - [-|rate/{sec|min}[:burst] You may 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
USER/GROUP (Optional) - [!][user-name-or-number][:group-name-or-number] This 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 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
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 ip6tables. 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
ip6tables.
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 Times are expressed in Local Civil Time (default).
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.

EXAMPLE

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: Allow all ssh and http connection requests from the internet to local system 2002:cec792b4:1::44: #ACTION SOURCE DEST PROTO DEST SOURCE ORIGINAL # PORT PORT(S) DEST DNAT net loc:2002:cec792b4:1::44 tcp ssh,http
Example 3: Allow http connection requests from the internet to local system 2002:cec792b4:1::44 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:<2002:cec792b4:1::44> tcp http - - 3/sec:10
Example 4: You want to accept SSH connections to your firewall only from internet IP addresses 2002:ce7c::92b4:1::2 and 2002:ce7c::92b4:1::22: #ACTION SOURCE DEST PROTO DEST SOURCE ORIGINAL # PORT PORT(S) DEST ACCEPT net:<2002:ce7c::92b4:1::2,2002:ce7c::92b4:1::22> \ $FW tcp 22

FILES

/etc/shorewall6/rules

NOTES

1. shorewall6-policy: shorewall6-policy.html; 2. shorewall6.conf
shorewall6.conf.html; 3. shorewall6-zones
shorewall6-zones.html; 4. shorewall6-nesting
shorewall6-nesting.html; 5. shorewall6-actions
shorewall6-actions.html; 6. shorewall6-exclusion
shorewall6-exclusion.html

docs.sk

comprehensive documentation repository

See also