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shorewall-policy(5)

NAME

   policy - Shorewall policy file

SYNOPSIS

   /etc/shorewall/policy

DESCRIPTION

   This file defines the high-level policy for connections between zones
   defined in shorewall-zones[1](5).

       Important
       The order of entries in this file is important

       This file determines what to do with a new connection request if we
       don't get a match from the /etc/shorewall/rules file . For each
       source/destination pair, the file is processed in order until a
       match is found ("all" will match any source or destination).

       Important
       Intra-zone policies are pre-defined

       For $FW and for all of the zones defined in /etc/shorewall/zones,
       the POLICY for connections from the zone to itself is ACCEPT (with
       no logging or TCP connection rate limiting) but may be overridden
       by an entry in this file. The overriding entry must be explicit
       (specifying the zone name in both SOURCE and DEST) or it must use
       "all+" (Shorewall 4.5.17 or later).

       Similarly, if you have IMPLICIT_CONTINUE=Yes in shorewall.conf,
       then the implicit policy to/from any sub-zone is CONTINUE. These
       implicit CONTINUE policies may also be overridden by an explicit
       entry in this file.

   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).

   SOURCE - zone[,...[+]]|$FW|all|all+
       Source zone. Must be the name of a zone defined in
       shorewall-zones[1](5), $FW, "all" or "all+".

       Support for "all+" was added in Shorewall 4.5.17. "all" does not
       override the implicit intra-zone ACCEPT policy while "all+" does.

       Beginning with Shorewall 5.0.12, multiple zones may be listed
       separated by commas. As above, if '+' is specified after two or
       more zone names, then the policy overrides the implicit intra-zone
       ACCEPT policy if the same zone appears in both the SOURCE and DEST
       columns.

   DEST - zone[,...[+]]|$FW|all|all+
       Destination zone. Must be the name of a zone defined in
       shorewall-zones[1](5), $FW, "all" or "all+". If the DEST is a bport
       zone, then the SOURCE must be "all", "all+", another bport zone
       associated with the same bridge, or it must be an ipv4 zone that is
       associated with only the same bridge.

       Support for "all+" was added in Shorewall 4.5.17. "all" does not
       override the implicit intra-zone ACCEPT policy while "all+" does.

       Beginning with Shorewall 5.0.12, multiple zones may be listed
       separated by commas. As above, if '+' is specified after two or
       more zone names, then the policy overrides the implicit intra-zone
       ACCEPT policy if the same zone appears in both the SOURCE and DEST
       columns.

   POLICY -
   {ACCEPT|DROP|REJECT|CONTINUE|QUEUE|NFQUEUE[(queuenumber1[:queuenumber2])]|NONE}[:{default-action-or-macro[:level]|None}]
       Policy if no match from the rules file is found.

       If the policy is neither CONTINUE nor NONE then the policy may be
       followed by ":" and one of the following:

        1. The word "None" or "none". This causes any default action
           defined in shorewall.conf[2](5) to be omitted for this policy.

        2. The name of an action. The action will be invoked before the
           policy is enforced.

       Actions can have parameters specified.

       Beginning with Shorewall 4.5.10, the action name can be followed
       optionally by a colon and a log level. The level will be applied to
       each rule in the action or body that does not already have a log
       level.

       Possible actions are:

       ACCEPT
           Accept the connection.

       DROP
           Ignore the connection request.

       REJECT
           For TCP, send RST. For all other, send an "unreachable" ICMP.

       QUEUE
           Queue the request for a user-space application such as
           Snort-inline.

       NFQUEUE
           Queue the request for a user-space application using the
           nfnetlink_queue mechanism. If a queuenumber1 is not given,
           queue zero (0) is assumed. Beginning with Shorewall 4.6.10, a
           second queue number (queuenumber2) may be given. This specifies
           a range of queues to use. Packets are then balanced across the
           given queues. This is useful for multicore systems: start
           multiple instances of the userspace program on queues x, x+1,
           .. x+n and use "x:x+n". Packets belonging to the same
           connection are put into the same nfqueue.

       CONTINUE
           Pass the connection request past any other rules that it might
           also match (where the source or destination zone in those rules
           is a superset of the SOURCE or DEST in this policy). See
           shorewall-nesting[3](5) for additional information.

       NONE
           Assume that there will never be any packets from this SOURCE to
           this DEST. Shorewall will not create any infrastructure to
           handle such packets and you may not have any rules with this
           SOURCE and DEST in the /etc/shorewall/rules file. If such a
           packet is received, the result is undefined. NONE may not be
           used if the SOURCE or DEST columns contain the firewall zone
           ($FW) or "all".

   LOG LEVEL (loglevel) - [log-level|ULOG|NFLOG]
       Optional - if supplied, each connection handled under the default
       POLICY is logged at that level. If not supplied, no log message is
       generated. See syslog.conf(5) for a description of log levels.

       You may also specify ULOG or NFLOG (must be in upper case). This
       will log to the ULOG or NFLOG target and will send to a separate
       log through use of ulogd
       (http://www.netfilter.org/projects/ulogd/index.html).

       For a description of log levels, see
       http://www.shorewall.net/shorewall_logging.html[4].

       If you don't want to log but need to specify the following column,
       place "-" here.

   BURST:LIMIT (limit) - [-|limit]
       where limit is one of:
           [-|[{s|d}:[[name]:]]]rate/{sec|min|hour|day}[:burst]
           [name1]:rate1/{sec|min|hour|day}[:burst1],[name2]:rate2/{sec|min|hour|day}[:burst2]
       If passed, specifies the maximum TCP connection rate and the size
       of an acceptable burst. If not specified, TCP connections are not
       limited. If the burst parameter is omitted, a value of 5 is
       assumed.

       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 give, the name shorewall is assumed. Where more
       than one POLICY or rule specifies the same name, the connections
       counts for the policies are aggregated and the individual rates
       apply to the aggregated count.

       Beginning with Shorewall 4.6.5, two limits may be specified,
       separated by a comma. In this case, the first limit (name1, rate1,
       burst1) specifies the per-source IP limit and the second limit
       specifies the per-destination IP limit.

       Example: client:10/sec:20,:60/sec:100

   CONNLIMIT - limit[:mask]
       May be used to limit the number of simultaneous connections from
       each individual host to limit connections. While the limit is only
       checked on connections to which this policy could apply, the number
       of current connections is calculated over all current connections
       from the SOURCE host. By default, the limit is applied to each host
       individually 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.

EXAMPLE

    1. All connections from the local network to the internet are allowed

    2. All connections from the internet are ignored but logged at syslog
       level KERNEL.INFO.

    3. All other connection requests are rejected and logged at level
       KERNEL.INFO.

               #SOURCE         DEST            POLICY          LOG           BURST:LIMIT
               #                                               LEVEL
               loc             net             ACCEPT
               net             all             DROP            info
               #
               # THE FOLLOWING POLICY MUST BE LAST
               #
               all             all             REJECT          info

FILES

   /etc/shorewall/policy

SEE ALSO

   http://www.shorewall.net/configuration_file_basics.htm#Pairs[5]

   shorewall(8), shorewall-accounting(5), shorewall-actions(5),
   shorewall-blacklist(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-rules(5),
   shorewall.conf(5), shorewall-secmarks(5), shorewall-tcclasses(5),
   shorewall-tcdevices(5), shorewall-mangle(5), shorewall-tos(5),
   shorewall-tunnels(5), shorewall-zones(5)

NOTES

    1. shorewall-zones
       http://www.shorewall.net/manpages/shorewall-zones.html

    2. shorewall.conf
       http://www.shorewall.net/manpages/shorewall.conf.html

    3. shorewall-nesting
       http://www.shorewall.net/manpages/shorewall-nesting.html

    4. http://www.shorewall.net/shorewall_logging.html
       http://www.shorewall.net/shorewall_logging.html

    5. http://www.shorewall.net/configuration_file_basics.htm#Pairs
       http://www.shorewall.net/configuration_file_basics.htm#Pairs



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