shorewall6.conf(5)
NAME
shorewall6.conf - Shorewall6 global configuration file
SYNOPSIS
/etc/shorewall6/shorewall6.conf
DESCRIPTION
This file sets options that apply to Shorewall6 as a whole. The file consists of Shell comments (lines beginning with '#'), blank lines and assignment statements (variable=value). If the value contains shell meta characters or white-space, then it must be enclosed in quotes. Example: LOG_LEVEL="NFLOG(1,0,1)".
OPTIONS
Many options have as their value a log-level. Log levels are a method
of describing to syslog (8) the importance of a message and a number of
parameters in this file have log levels as their value.
These levels are defined by syslog and are used to determine the
destination of the messages through entries in /etc/syslog.conf (5).
The syslog documentation refers to these as "priorities"; Netfilter
calls them "levels" and Shorewall6 also uses that term.
Valid levels are:
7 debug
6 info
5 notice
4 warning
3 err
2 crit
1 alert
0 emerg
For most Shorewall6 logging, a level of 6 (info) is appropriate.
Shorewall6 log messages are generated by NetFilter and are logged using
facility 'kern' and the level that you specify. If you are unsure of
the level to choose, 6 (info) is a safe bet. You may specify levels by
name or by number.
If you have built your kernel with NFLOG target support, you may also
specify a log level of NFLOG (must be all caps). Rather than log its
messages to syslogd, Shorewall6 will direct netfilter to log the
messages via the NFLOG target which will send them to a process called
'ulogd'. ulogd is available with most Linux distributions (although it
probably isn't installed by default). Ulogd is also available from
http://www.netfilter.org/projects/ulogd/index.html and can be
configured to log all Shorewall6 message to their own log file
Note
If you want to specify parameters to ULOG or NFLOG (e.g.,
NFLOG(1,0,1)), then you must quote the setting.
Example:
MACLIST_LOG_LEVEL="NFLOG(1,0,1)"
Beginning with Shorewall 5.0.0, the log level may be followed by a
colon (":") and a log tag. The log tag normally follows the packet
disposition in Shorewall-generated Netfilter log messages, separated
from the disposition by a colon (e.g, "DROP:mytag"). See LOGTAGONLY
below for additional information.
The following options may be set in shorewall6.conf.
ACCEPT_DEFAULT={action[(parameters)][:level]|none}
DROP_DEFAULT={action[(parameters)][:level]|none}
NFQUEUE_DEFAULT={action[(parameters)][:level]|none}
QUEUE_DEFAULT={action[(parameters)][:level]|none}
REJECT_DEFAULT={action[(parameters)][:level]|none}
DROP_DEFAULT describes the rules to be applied before a connection
request is dropped by a DROP policy; REJECT_DEFAULT describes the
rules to be applied if a connection request is rejected by a REJECT
policy. The other three are similar for ACCEPT, QUEUE and NFQUEUE
policies.
The value applied to these may be:
a) The name of an action. The
name may optionally be followed by a
comma-separated list of
parameters enclosed in parentheses if the specified
action accepts
parameters (e.g., 'Drop(audit)').
c) None or none
The default values are:
DROP_DEFAULT="Drop"
REJECT_DEFAULT="Reject"
ACCEPT_DEFAULT="none"
QUEUE_DEFAULT="none"
NFQUEUE_DEFAULT="None"
If you set the value of either option to "None" then no default
action will be used and the default action or macro must be
specified in shorewall6-policy[1](5).
You can pass parameters to the specified action or macro (e.g.,
myaction(audit,DROP)).
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 macro body that does not already have a
log level.
ACCOUNTING=[Yes|No]
Added in Shorewall 4.4.7. If set to Yes, Shorewall6 accounting is
enabled (see shorewall6-accounting[2](5)). If not specified or set
to the empty value, ACCOUNTING=Yes is assumed.
ACCOUNTING_TABLE=[filter|mangle]
Added in Shorewall 4.4.20. This setting determines which Netfilter
table the accounting rules are added in. By default,
ACCOUNTING_TABLE=filter is assumed. See also
shorewall6-accounting[2](5).
ADMINISABSENTMINDED=[Yes|No]
The value of this variable affects Shorewall's stopped state. The
behavior differs depending on whether shorewall-routestopped[3](5)
or shorewall-stoppedrules[4](5) is used:
routestopped
When ADMINISABSENTMINDED=No, only traffic to/from those
addresses listed in routestopped is accepted when Shorewall is
stopped. When ADMINISABSENTMINDED=Yes, in addition to traffic
to/from addresses in routestopped, connections that were active
when Shorewall stopped continue to work and all new connections
from the firewall system itself are allowed.
Note that the routestopped file is not supported in Shorewall
5.0 and later versions.
stoppedrules
All existing connections continue to work. To sever all
existing connections when the firewall is stopped, install the
conntrack utility and place the command conntrack -F in the
stopped user exit (/etc/shorewall6/stopped).
If ADMINISABSENTMINDED=No, only new connections matching
entries in stoppedrules are accepted when Shorewall is stopped.
Response packets and related connections are automatically
accepted.
If ADMINISABSENTMINDED=Yes, in addition to connections matching
entries in stoppedrules, all new connections from the firewall
system itself are allowed when the firewall is stopped.
Response packets and related connections are automatically
accepted.
If this variable is not set or is given the empty value then
ADMINISABSENTMINDED=No is assumed.
IGNOREUNKNOWNVARIABLES=[Yes|No]
Added in Shorewall 4.5.11. Normally, if an unknown shell variable
is encountered in a configuration file (except in ?IF and ?ELSIF
directives), the compiler raises a fatal error. If
IGNOREUNKNOWNVARIABLES is set to Yes, then such variables simply
expand to an empty string. Default is No.
AUTOCOMMENT=[Yes|No]
Formerly named AUTO_COMMENT. If set, if there is not a current
comment when a macro is invoked, the behavior is as if the first
line of the macro file was "COMMENT <macro name>". The AUTO_COMMENT
option has a default value of 'Yes'.
AUTOHELPERS=[Yes|No]
Added in Shorewall 4.5.7. When set to Yes (the default), the
generated ruleset will automatically associate helpers with
applications that require them (FTP, IRC, etc.). When configuring
your firewall on systems running kernel 3.5 or later, it is
recommended that you:
1. Set AUTOHELPERS=No.
2. Modify the HELPERS setting (see below) to list the helpers that
you need.
3. Either:
1. Modify shorewall6-conntrack[5] (5) to only apply helpers
where they are required; or
2. Specify the appropriate helper in the HELPER column in
shorewall6-rules[6] (5).
Note
The macros for those applications requiring a helper
automatically specify the appropriate HELPER where
required.
AUTOMAKE=[Yes|No]
If set, the behavior of the start, reload and restart commands is
changed; if no files in the CONFIG_PATH (see below) have been
changed since the last successful start, reload or restart command,
then the compilation step is skipped and the compiled script that
executed the last start, reload or restart command is used. The
default is AUTOMAKE=No.
The setting of the AUTOMAKE option is ignored if the start, reload
or restart command includes a directory name (e.g., shorewall6
restart /etc/shorewall.new).
BASIC_FILTERS=[Yes|No]
Added in Shorewall-4.6.0. When set to Yes, causes entries in
shorewall6-tcfilters(5)[7] to generate a basic filter rather than a
u32 filter. This setting requires the Basic Ematch capability in
your kernel and iptables.
Note
One of the advantages of basic filters is that ipset matches
are supported in newer iproute2 and kernel versions. Because
Shorewall6 cannot reliably detect this capability, use of basic
filters is controlled by this option.
The default value is No which causes u32 filters to be generated.
BLACKLIST=[{ALL|state[,...]}]
where state is one of NEW, ESTABLISHED, RELATED, INVALID,or
UNTRACKED.
Added in Shorewall 4.5.13 to replace the BLACKLISTNEWONLY option.
Specifies the connection tracking states that are to be subject to
blacklist screening. If BLACKLIST is not specified then the states
subject to blacklisting are NEW,ESTABLISHED,INVALID,UNTRACKED.
Note: The ESTABLISHED state may not be specified if FASTACCEPT is
specified.
BLACKLIST_DISPOSITION=[DROP|A_DROP|REJECT|A_REJECT]
This parameter determines the disposition of packets from
blacklisted hosts. It may have the value DROP if the packets are to
be dropped or REJECT if the packets are to be replied with an ICMP
port unreachable reply or a TCP RST (tcp only). If you do not
assign a value or if you assign an empty value then DROP is
assumed. The setting determines the disposition of packets sent to
the blacklog target of shorewall6-blrules[8](5).
BLACKLIST_LOG_LEVEL=[log-level[:log-tag]]
Formerly named BLACKLIST_LOGLEVEL. This parameter determines if
packets from blacklisted hosts are logged and it determines the
syslog level that they are to be logged at. Its value is a syslog
level (Example: BLACKLIST_LOG_LEVEL=debug). If you do not assign a
value or if you assign an empty value then packets from blacklisted
hosts are not logged. The setting determines the log level of
packets sent to the blacklog target of shorewall6-blrules[8](5).
CHAIN_SCRIPTS={Yes|No}
Added in Shorewall 4.5.16. Prior to the availability of BEGIN
PERL....END PERL in configuration files, the only way to execute a
chain-specific script was to create a script file with the same
name as the chain and place it in a directory on the CONFIG_PATH.
That facility has the drawback that the compiler will attempt to
run a non-script file just because it has the same name as a chain.
To disable this facility, set CHAIN_SCRIPTS=No. If not specified or
specified as the empty value, CHAIN_SCRIPTS=Yes is assumed.
CLAMPMSS=[Yes|No|value]
This parameter enables the TCP Clamp MSS to PMTU feature of
Netfilter and is usually required when your internet connection is
through PPPoE or PPTP. If set to Yes or yes, the feature is
enabled. If left blank or set to No or no, the feature is not
enabled.
Important: This option requires CONFIG_IP_NF_TARGET_TCPMSS in your
kernel.
You may also set CLAMPMSS to a numeric value (e.g., CLAMPMSS=1400).
This will set the MSS field in TCP SYN packets going through the
firewall to the value that you specify.
CLEAR_TC=[Yes|No]
If this option is set to No then Shorewall6 won't clear the current
traffic control rules during [re]start or reload. This setting is
intended for use by people that prefer to configure traffic shaping
when the network interfaces come up rather than when the firewall
is started. If that is what you want to do, set TC_ENABLED=Yes and
CLEAR_TC=No and do not supply an /etc/shorewall6/tcstart file. That
way, your traffic shaping rules can still use the "fwmark"
classifier based on packet marking defined in
shorewall6-tcrules[9](5). If not specified, CLEAR_TC=No is assumed.
Warning
If you also run Shorewall and if you have TC_ENABLED=Internal
in your shorewall-conf[10](5), then you will want CLEAR_TC=No
in this file.
COMPLETE=[Yes|No]
Added in Shorewall6 4.4.12. When you set this option to Yes, you
are asserting that the configuration is complete so that your set
of zones encompasses any hosts that can send or receive traffic
to/from/through the firewall. This causes Shorewall6 to omit the
rules that catch packets in which the source or destination IP
address is outside of any of your zones. Default is No. It is
recommended that this option only be set to Yes if:
* You have defined an interface whose effective physical setting
is '+'.
* That interface is assigned to a zone.
* You have no CONTINUE policies or rules.
CONFIG_PATH=[directory[:directory]...]
Specifies where configuration files other than shorewall6.conf may
be found. CONFIG_PATH is specifies as a list of directory names
separated by colons (":"). When looking for a configuration file:
* If the command is "try" or a "<configuration directory>" was
specified in the command (e.g., shorewall6 check ./gateway)
then the directory given in the command is searched first.
* Next, each directory in the CONFIG_PATH setting is searched in
sequence.
If CONFIG_PATH is not given or if it is set to the empty value then
the contents of /usr/share/shorewall6/configpath are used. As
released from shorewall.net, that file sets the CONFIG_PATH to
/etc/shorewall6:/usr/share/shorewall6:/usr/share/shorewall but your
particular distribution may set it differently. See the output of
shorewall6 show config for the default on your system.
DEFER_DNS_RESOLUTION=[Yes|No]
Added in Shorewall 4.5.12. When set to 'Yes' (the default), DNS
names are validated in the compiler and then passed on to the
generated script where they are resolved by ip6tables-restore. This
is an advantage if you use AUTOMAKE=Yes and the IP address
associated with the DNS name is subject to change. When
DEFER_DNS_RESOLUTION=No, DNS names are converted into IP addresses
by the compiler. This has the advantage that when AUTOMAKE=Yes the
start, reload and restart commands will succeed even if no DNS
server is reachable (assuming that the configuration hasn't changed
since the compiled script was last generated).
DELETE_THEN_ADD={Yes|No}
If set to Yes (the default value), entries in the
/etc/shorewall6/rtrules file cause an 'ip rule del' command to be
generated in addition to an 'ip rule add' command. Setting this
option to No, causes the 'ip rule del' command to be omitted.
DONT_LOAD=[module[,module]...]
Causes Shorewall6 to not load the listed kernel modules.
DYNAMIC_BLACKLIST={Yes|No||ipset[-only][,option[,...]][:[setname][:log_level|:log_tag]]]}
Added in Shorewall 4.4.7. When set to No or no, chain-based dynamic
blacklisting using shorewall6 drop, shorewall6 reject, shorewall6
logdrop and shorewall6 logreject is disabled. Default is Yes.
Beginning with Shorewall 5.0.8, ipset-based dynamic blacklisting
using shorewall6 blacklist is also supported. The name of the set
(setname) and the level (log_level), if any, at which blacklisted
traffic is to be logged may also be specified. The default set name
is SW_DBL6 and the default log level is none (no logging). if
ipset-only is given, then chain-based dynamic blacklisting is
disabled just as if DYNAMIC_BLACKLISTING=No had been specified.
Possible options are:
src-dst
Normally, only packets whose source address matches an entry in
the ipset are dropped. If src-dst is included, then packets
whose destination address matches an entry in the ipset are
also dropped.
disconnect
The disconnect option was added in Shorewall 5.0.13 and
requires that the conntrack utility be installed on the
firewall system. When an address is blacklisted using the
blacklist command, all connections originating from that
address are disconnected. if the src-dst option was also
specified, then all connections to that address are also
disconnected.
timeout=seconds
Added in Shorewall 5.0.13. Normally, Shorewall creates the
dynamic blacklisting ipset with timeout 0 which means that
entries are permanent. If you want entries in the set that are
not accessed for a period of time to be deleted from the set,
you may specify that period using this option. Note that the
blacklist command can override the ipset's timeout setting.
Important
Once the dynamic blacklisting ipset has been created,
changing this option setting requires a complete restart of
the firewall; shorewall6 restart if RESTART=restart,
otherwise shorewall6 stop && shorewall6 start
When ipset-based dynamic blacklisting is enabled, the contents of
the blacklist will be preserved over stop/reboot/start sequences if
SAVE_IPSETS=Yes or if setname is included in the list of sets to be
saved in SAVE_IPSETS.
EXPAND_POLICIES={Yes|No}
Normally, when the SOURCE or DEST columns in shorewall-policy(5)
contains 'all', a single policy chain is created and the policy is
enforced in that chain. For example, if the policy entry is
#SOURCE DEST POLICY LOG
# LEVEL
net all DROP info
then the chain name is 'net-all' ("net2all" if ZONE2ZONE=2) which
is also the chain named in Shorewall log messages generated as a
result of the policy. If EXPAND_POLICIES=Yes, then Shorewall will
create a separate chain for each pair of zones covered by the
policy. This makes the resulting log messages easier to interpret
since the chain in the messages will have a name of the form 'a2b'
where 'a' is the SOURCE zone and 'b' is the DEST zone.
EXPORTMODULES=[Yes|No]
Added in Shorewall 4.4.17. When set to Yes when compiling for use
by Shorewall6 Lite (shorewall6 load, shorewall6 reload or
shorewall6 export commands), the compiler will copy the modules or
helpers file from the administrative system into the script. When
set to No or not specified, the compiler will not copy the modules
or helpers file from /usr/share/shorewall6 but will copy those
found in another location on the CONFIG_PATH.
When compiling for direct use by Shorewall6, causes the contents of
the local module or helpers file to be copied into the compiled
script. When set to No or not set, the compiled script reads the
file itself.
FASTACCEPT={Yes|No}
Normally, Shorewall6 defers accepting ESTABLISHED/RELATED packets
until these packets reach the chain in which the original
connection was accepted. So for packets going from the 'loc' zone
to the 'net' zone, ESTABLISHED/RELATED packets are ACCEPTED in the
'loc-net' or 'loc2net' chain, depending on the setting of ZONE2ZONE
(see below).
If you set FASTACCEPT=Yes, then ESTABLISHED/RELATED packets are
accepted early in the INPUT, FORWARD and OUTPUT chains. If you set
FASTACCEPT=Yes then you may not include rules in the ESTABLISHED or
RELATED sections of shorewall6-rules[6](5).
FIREWALL=[dnsname-or-ip-address]
This option was added in Shorewall 5.0.13 and may be used on an
administrative system in directories containing the configurations
of remote firewalls. The contents of the variable are the default
value for the system parameter to the remote-start, remote-reload
and remote-restart commands.
FORWARD_CLEAR_MARK={Yes|No}
Added in Shorewall 4.4.11. Traditionally, Shorewall has cleared the
packet mark in the first rule in the mangle FORWARD chain. This
behavior is maintained with the default setting of this option
(FORWARD_CLEAR_MARK=Yes). If FORWARD_CLEAR_MARK is set to 'No',
packet marks set in the mangle PREROUTING chain are retained in the
FORWARD chains.
GEOIPDIR=[pathname]
Added in Shorewall 4.5.4. Specifies the pathname of the directory
containing the GeoIP Match database. See
http://www.shorewall.net/ISO-3661.html[11]. If not specified, the
default value is /usr/share/xt_geoip/LE which is the default
location of the little-endian database.
HELPERS=[helper[,helper...]]
Added in Shorewall 4.5.7. This option specifies a comma-separated
list naming the Netfilter application helpers that are to be
enabled. If not specified, the default is to enable all helpers.
Possible values for helper are:
* amanda
* ftp
* h323
* irc
* netbios-ns
* none - This special value was added in Shorewall 4.5.16 and
indicates that no helpers are to be enabled. It also prevents
the compiler for probing for helper support; such probing
generates messages on the system log of the form "xt_CT: No
such helper XXX" where XXX is the helper name. When used, none
must be the only helper specified.
* pptp
* sane
* sip
* snmp
* tftp
When HELPERS is specified on a system running Kernel 3.5.0 or
later, automatic association of helpers to connections is disabled.
IMPLICIT_CONTINUE={Yes|No}
When this option is set to Yes, it causes subzones to be treated
differently with respect to policies.
Subzones are defined by following their name with ":" and a list of
parent zones (in shorewall6-zones[12](5)). Normally, you want to
have a set of special rules for the subzone and if a connection
doesn't match any of those subzone-specific rules then you want the
parent zone rules and policies to be applied; see
shorewall6-nesting[13](5). With IMPLICIT_CONTINUE=Yes, that happens
automatically.
If IMPLICIT_CONTINUE=No or if IMPLICIT_CONTINUE is not set, then
subzones are not subject to this special treatment. With
IMPLICIT_CONTINUE=Yes, an implicit CONTINUE policy may be
overridden by including an explicit policy (one that does not
specify "all" in either the SOURCE or the DEST columns).
INLINE_MATCHES={Yes|No}
Added in Shorewall 4.6.0. Traditionally in shorewall6-rules[6](5),
a semicolon separates column-oriented specifications on the left
from alternative specificaitons[14] on the right.. When
INLINE_MATCHES=Yes is specified, the specifications on the right
are interpreted as if INLINE had been specified in the ACTION
column. This also applies to shorewall6-masq(5)[15] and
shorewall6-mangle(5[16]) which also support INLINE. If not
specified or if specified as the empty value, the value 'No' is
assumed for backward compatibility.
Beginning with Shorewall 5.0.0, it is no longer necessary to set
INLINE_MATCHES=Yes in order to be able to specify your own iptables
text in a rule and INLINE_MATCHES=Yes is deprecated. Beginning with
5.0.0, you may simply preface your text with a pair of semicolons
(";;"). If alternate input is also specified in the rule, it should
appear before the semicolons and may be separated from normal
column input by a single semicolon or enclosed in curly braces
("{....}").
INVALID_DISPOSITION=[A_DROP|A_REJECT|DROP|REJECT|CONTINUE]
Added in Shorewall 4.5.13. Shorewall has traditionally passed
INVALID packets through the NEW section of shorewall-rules[6] (5).
When a packet in INVALID state fails to match any rule in the
INVALID section, the packet is disposed of based on this setting.
The default value is CONTINUE for compatibility with earlier
versions.
INVALID_LOG_LEVEL=log-level[:log-tag]
Added in Shorewall 4.5.13. Packets in the INVALID state that do not
match any rule in the INVALID section of shorewall6-rules[6] (5)
are logged at this level. The default value is empty which means no
logging is performed.
IP=[pathname]
If specified, gives the pathname of the 'ip' executable. If not
specified, 'ip' is assumed and the utility will be located using
the current PATH setting.
IP_FORWARDING=[On|Off|Keep]
This rather useless parameter determines whether Shorewall6 enables
or disables IPV6 Packet Forwarding on all interfaces
(/proc/sys/net/ipv6/config/all/forwarding). Possible values are:
On or on
packet forwarding will be enabled.
Off or off
packet forwarding will be disabled.
Keep or keep
Shorewall6 will neither enable nor disable packet forwarding
If this variable is not set or is given an empty value
(IP_FORWARD="") then IP_FORWARD=On is assumed.
IP6TABLES=[pathname]
This parameter names the ip6tables executable to be used by
Shorewall6. If not specified or if specified as a null value, then
the ip6tables executable located using the PATH option is used.
Regardless of how the ip6tables utility is located (specified via
IP6TABLES= or located via PATH), Shorewall6 uses the
ip6tables-restore and ip6tables-save utilities from that same
directory.
IPSET=[pathname]
If specified, gives the pathname of the 'ipset' executable. If not
specified, 'ipset' is assumed and the utility will be located using
the current PATH setting.
IPSET_WARNINGS={Yes|No}
Added in Shorewall 4.5.2. Default is Yes. When set, causes the
rules compiler to issue a warning when:
* The compiler is being run by root and an ipset specified in the
configuration does not exists. Only one warning is issued for
each missing ipset.
* When [src] is specified in a destination column and when [dst]
is specified in a source column.
KEEP_RT_TABLES={Yes|No}
When set to Yes, this option prevents scripts generated by
Shorewall6 from altering the /etc/iproute2/rt_tables database when
there are entries in /etc/shorewall6/providers. If you set this
option to Yes while Shorewall6 (Shorewall6-lite) is running, you
should remove the file /var/lib/shorewall6/rt_tables
(/var/lib/shorewall6-lite/rt_tables) before your next stop,
refresh, restore, reload or restart command.
The default is KEEP_RT_TABLES=No.
LOAD_HELPERS_ONLY={Yes|No}
Added in Shorewall 4.4.7. When set to Yes, restricts the set of
modules loaded by shorewall to those listed in
/var/lib/shorewall6/helpers and those that are actually used. When
not set, or set to the empty value, LOAD_HELPERS_ONLY=No is
assumed.
LOCKFILE=[pathname]
Specifies the name of the Shorewall6 lock file, used to prevent
simultaneous state-changing commands. If not specified,
${VARDIR}/shorewall6/lock is assumed (${VARDIR} is normally
/var/lib but can be changed when Shorewall-core is installed -- see
the output of shorewall6 show vardir).
LOG_BACKEND=[backend]
Added in Shorewall 4.6.4. LOG_BACKEND determines the logging
backend to be used for the iptrace command (see shorewall6(8)[17]).
backend is one of:
LOG
Use standard kernel logging.
netlink
Use netlink logging to ulogd version 2 or later.
LOG_VERBOSITY=[number]
This option controls the amount of information logged to the file
specified in the STARTUP_LOG option.
Values are:
-1 - Logging is disabled
0 - Silent. Only error messages are logged.
1 - Major progress messages logged.
2 - All progress messages logged
If not specified, then -1 is assumed.
LOGALLNEW=[log-level]
This option is intended for use as a debugging aid. When set to a
log level, this option causes Shorewall6 to generate a logging rule
as the first rule in each builtin chain.
* The table name is used as the chain name in the log prefix.
* The chain name is used as the target in the log prefix.
For example, using the default LOGFORMAT, the log prefix for
logging from the nat table's PREROUTING chain is:
Shorewall:nat:PREROUTING
Important
To help insure that all packets in the NEW state are logged,
rate limiting (LOGLIMIT) should be disabled when using
LOGALLNEW. Use LOGALLNEW at your own risk; it may cause high
CPU and disk utilization and you may not be able to control
your firewall after you enable this option.
Caution
Do not use this option if the resulting log messages will be
sent to another system.
LOGFILE=[pathname|systemd]
This parameter tells the /sbin/shorewall6 program where to look for
Shorewall6 messages when processing the dump, logwatch, show log,
and hits commands. If not assigned or if assigned an empty value,
/var/log/messages is assumed. Beginning with Shorewall 5.0.10.1,
you may specify systemd to use journelctl -r to read the log.
LOGFORMAT=["formattemplate"]
The value of this variable generate the --log-prefix setting for
Shorewall6 logging rules. It contains a "printf" formatting
template which accepts three arguments (the chain name, logging
rule number (optional) and the disposition). To use LOGFORMAT with
fireparse, set it as:
LOGFORMAT="fp=%s:%d a=%s "
If the LOGFORMAT value contains the substring "%d" then the logging
rule number is calculated and formatted in that position; if that
substring is not included then the rule number is not included. If
not supplied or supplied as empty (LOGFORMAT="") then
"Shorewall6:%s:%s:" is assumed.
Note
The setting of LOGFORMAT has an effect of the permitted length
of zone names. See shorewall6-zones[12] (5).
LOGLIMIT=[[{s|d}:]rate/{sec|second|min|minute|hour|day}[:burst]]
Added in Shorewall 4.4.12. Limits the logging rate, either overall,
or by source or destination IP address.
If the value starts with 's:' then logging is limited per source
IP. If the value starts with 'd:', then logging is limited per
destination IP. Otherwise, the overall logging rate is limited.
If burst is not specified, then a value of 5 is assumed.
The keywords second and minute are accepted beginning with
Shorewall 4.6.13.
LOGTAGONLY=[Yes|No]
Using the default LOGFORMAT, chain names may not exceed 11
characters or truncation of the log prefix may occur. Longer chain
names may be used with log tags if you set LOGTAGONLY=Yes. With
LOGTAGONLY=Yes, if a log tag is specified then the tag is included
in the log prefix in place of the chain name.
Beginning with Shorewall 4.5.12, when LOGTAGONLY=Yes, you have more
control over the generated log prefix. Beginning with that release,
the tag is interpreted as a chain name and a disposition separated
by a comma. So this rule:
#ACTION SOURCE DEST
LOG:info:foo,bar net fw
would generate the following log prefix when using the default
LOGFORMAT setting:
Shorewall:foo:bar:
Similarly,
#ACTION SOURCE DEST
LOG:info:,bar net fw
would generate
Shorewall:net2fw:bar:
MACLIST_DISPOSITION=[ACCEPT|DROP|REJECT|A_DROP|A_REJECT]
Determines the disposition of connections requests that fail MAC
Verification and must have the value ACCEPT (accept the connection
request anyway), REJECT (reject the connection request) or DROP
(ignore the connection request). If not set or if set to the empty
value (e.g., MACLIST_DISPOSITION="") then
MACLIST_DISPOSITION=REJECT is assumed.
A_DROP and A_REJECT are audited versions of DROP and REJECT
respectively and were added in Shorewall 4.4.20. They require
AUDIT_TARGET in the kernel and ip6tables.
MACLIST_LOG_LEVEL=[log-level[:log-tag]]
Determines the syslog level for logging connection requests that
fail MAC Verification. The value must be a valid syslogd log level.
If you don't want to log these connection requests, set to the
empty value (e.g., MACLIST_LOG_LEVEL="").
MACLIST_TABLE=[filter|mangle]
Normally, MAC verification occurs in the filter table (INPUT and
FORWARD) chains. When forwarding a packet from an interface with
MAC verification to a bridge interface, that doesn't work.
This problem can be worked around by setting MACLIST_TABLE=mangle
which will cause Mac verification to occur out of the PREROUTING
chain. Because REJECT isn't available in that environment, you may
not specify MACLIST_DISPOSITION=REJECT with MACLIST_TABLE=mangle.
MACLIST_TTL=[number]
The performance of configurations with a large numbers of entries
in shorewall6-maclist[18](5) can be improved by setting the
MACLIST_TTL variable in shorewall6.conf[19](5).
If your iptables and kernel support the "Recent Match" (see the
output of "shorewall check" near the top), you can cache the
results of a 'maclist' file lookup and thus reduce the overhead
associated with MAC Verification.
When a new connection arrives from a 'maclist' interface, the
packet passes through then list of entries for that interface in
shorewall6-maclist[18](5). If there is a match then the source IP
address is added to the 'Recent' set for that interface. Subsequent
connection attempts from that IP address occurring within
$MACLIST_TTL seconds will be accepted without having to scan all of
the entries. After $MACLIST_TTL from the first accepted connection
request from an IP address, the next connection request from that
IP address will be checked against the entire list.
If MACLIST_TTL is not specified or is specified as empty (e.g,
MACLIST_TTL="" or is specified as zero then 'maclist' lookups will
not be cached).
MANGLE_ENABLED=[Yes|No]
Determines whether Shorewall will generate rules in the Netfilter
mangle table. Setting MANGLE_ENABLED=No disables all Shorewall
features that require the mangle table. The default is
MANGLE_ENABLED=Yes.
MARK_IN_FORWARD_CHAIN=[Yes|No]
If your kernel has a FORWARD chain in the mangle table, you may set
MARK_IN_FORWARD_CHAIN=Yes to cause the marking specified in the
tcrules file to occur in that chain rather than in the PREROUTING
chain. This permits you to mark inbound traffic based on its
destination address when DNAT is in use. To determine if your
kernel has a FORWARD chain in the mangle table, use the /shorewall6
show mangle command; if a FORWARD chain is displayed then your
kernel will support this option. If this option is not specified or
if it is given the empty value (e.g., MARK_IN_FORWARD_CHAIN="")
then MARK_IN_FORWARD_CHAIN=No is assumed.
MASK_BITS=[number]
Added in Shorewall 4.4.26. Number of bits on the right of the
32-bit packet mark to be masked when clearing the traffic shaping
mark. Must be >= TC_BITS and <= PROVIDER_OFFSET (if PROVIDER_OFFSET
> 0). Prior to Shorewall 5.0.0, default value and the default
values of the other mark layout options is determined as follows:
Table 1. Default Packet Mark Layout
WIDE_TC_MARKS=No, TC_BITS=8,
HIGH_ROUTE_MARKS=No PROVIDER_BITS=8,
PROVIDER_OFFSET=0,
MASK_BITS=8
WIDE_TC_MARKS=No, TC_BITS=8, PROVIDER_BITS=8,
HIGH_ROUTE_MARKS=Yes PROVIDER_OFFSET=8,
MASK_BITS=8
WIDE_TC_MARKS=Yes, TC_BITS=14, PROVIDER_BITS=8,
HIGH_ROUTE_MARKS=No PROVIDER_OFFSET=0,
MASK_BITS=16
WIDE_TC_MARKS=Yes, TC_BITS=14, PROVIDER_BITS=8,
HIGH_ROUTE_MARKS=Yes PROVIDER_OFFSET=16,
MASK_BITS=16
From 5.0.0 onward, the default value of MASK_BITS is 8, the default
value of PROVIDER_BITS, TC_BITS, MASK_BITS and PROVIDER_OFFSET is
8.
MODULE_SUFFIX=["extension ..."]
The value of this option determines the possible file extensions of
kernel modules. The default value is "ko ko.gz ko.xz o o.gz o.xz gz
xz".
MODULESDIR=[[+]pathname[:pathname]...]
This parameter specifies the directory/directories where your
kernel netfilter modules may be found. If you leave the variable
empty, Shorewall will supply the value
"/lib/modules/$uname/kernel/net/ipv${g_family}/netfilter:/lib/modules/$uname/kernel/net/netfilter:/lib/modules/$uname/kernel/net/sched:/lib/modules/$uname/extra:/lib/modules/$uname/extra/ipset"
where uname holds the output of 'uname -r' and g_family holds '6'.
The option plus sign ('+') was added in Shorewall 5.0.3 and causes
the listed pathnames to be appended to the default list above.
MUTEX_TIMEOUT=[seconds]
The value of this variable determines the number of seconds that
programs will wait for exclusive access to the Shorewall6 lock
file. After the number of seconds corresponding to the value of
this variable, programs will assume that the last program to hold
the lock died without releasing the lock.
If not set or set to the empty value, a value of 60 (60 seconds) is
assumed.
An appropriate value for this parameter would be twice the length
of time that it takes your firewall system to process a shorewall6
restart command.
NFACCT=[pathname]
Added in Shorewall 4.5.7. Specifies the pathname of the nfacct
utility. If not specified, Shorewall will use the PATH setting to
find the program.
OPTIMIZE=[value]
The specified value enables certain optimizations. Each
optimization category is associated with a power of two. To enable
multiple optimization categories, simply add their corresponding
numbers together.
Beginning with Shorewall 4.5.20, you may specify OPTIMIZE=All to
enable all optimization categories, and you may also specify
OPTIMIZE=None to disable optimization.
* Optimization category 1 - Traditionally, Shorewall has created
rules for the complete matrix of host groups defined by the
zones, interfaces and hosts files[20]. Any traffic that didn't
correspond to an element of that matrix was rejected in one of
the built-in chains. When the matrix is sparse, this results in
lots of largely useless rules.
These extra rules can be eliminated by setting the 1 bit in
OPTIMIZE.
The 1 bit setting also controls the suppression of redundant
wildcard rules (those specifying "all" in the SOURCE or DEST
column). A wildcard rule is considered to be redundant when it
has the same ACTION and Log Level as the applicable policy.
Note
Optimization level 1 is ignored when optimization level 4
is also selected, since level 4 performs similar
optimizations in a more robust way.
* Optimization category 2 - Added in Shorewall 4.4.7. When set,
suppresses superfluous ACCEPT rules in a policy chain that
implements an ACCEPT policy. Any ACCEPT rules that immediately
precede the final blanket ACCEPT rule in the chain are now
omitted.
* Optimization category 4 - Added in Shorewall 4.4.7. When set,
causes short chains (those with less than 2 rules) to be
optimized away. The following chains are excluded from
optimization:
* accounting chains (unless OPTIMIZE_ACCOUNTING=Yes)
* action chains (user-defined)
* 'blacklst' chain
* dynamic
Additionally:
* If a built-in chain has a single rule that branches to a
second chain, then the rules from the second chain are
moved to the built-in chain and the target chain is
omitted.
* Chains with no references are deleted.
* Accounting chains are subject to optimization if the
OPTIMIZE_ACCOUNTING option is set to 'Yes'.
* If a chain ends with an unconditional branch to a second
chain (other than to 'reject'), then the branch is deleted
from the first chain and the rules from the second chain
are appended to it.
An additional optimization was added in Shorewall 4.5.4. If the
last rule in a chain is an unqualified jump to a simple target,
then all immediately preceding rules with the same simple
target are omitted.
For example, consider this chain:
-A fw-net -p udp --dport 67:68 -j ACCEPT
-A fw-net -p udp --sport 1194 -j ACCEPT
-A fw-net -p 41 -j ACCEPT
-A fw-net -j ACCEPT
Since all of the rules are jumps to the simple target ACCEPT,
this chain is totally optimized away and jumps to the chain are
replace with jumps to ACCEPT.
* Optimization category 8 - Added in Shorewall 4.4.9. When set,
causes chains with identical rules to be collapsed into a
single chain.
* Optimization category 16 - Added in Shorewall 4.4.26. When set,
causes sequences of compatible rules to be combined into a
single rule. Rules are considered compatible if they differ
only in their destination ports and comments.
A sequence of compatible rules is often generated when macros
are invoked in sequence.
The ability to combine adjacent rules is limited by two
factors:
* Destination port lists may only be combined up to a maximum
of 15 ports, where a port-pair counts as two ports.
* Rules may only be combined until the length of their
concatenated comment reaches 255 characters.
When either of these limits would be exceeded, the current
combined rule is emitted and the compiler attempts to combine
rules beginning with the one that would have exceeded the
limit. Adjacent combined comments are separated by ', '. Empty
comments at the front of a group of combined comments are
replaced by 'Others and'. Empty comments at the end of a group
of combined comments are replaced by 'and others'.
Beginning in Shorewall 4.5.10, this option also suppresses
duplicate adjacent rules and duplicate non-adjacent rules that
don't include mark, connmark, dscp, ecn, set, tos or u32
matches.
Example 1:
Rules with comments "FOO", <empty> and "BAR" would result
in the combined comment "FOO and others, BAR".
Example 2:
Rules with comments <empty>, "FOO" and "BAR" would result
in the combined comment "Others and FOO, BAR". Note:
Optimize level 16 requires "Extended Multi-port Match" in
your iptables and kernel.
The default value is zero which disables all optimizations.
OPTIMIZE_ACCOUNTING=[Yes|No]
Added in Shorewall 4.4.7. If set to Yes, Shorewall accounting
changes are subject to optimization (OPTIMIZE=4,5,6 or 7). If not
specified or set to the empty value, OPTIMIZE_ACCOUNTING=No is
assumed.
PAGER=pathname
Added in Shorewall 5.0.6. Specifies a path name of a pager program
like less or more. When PAGER is given, the output of verbose
status commands and the dump command are piped through the named
program when the output file is a terminal.
Beginning with Shorewall 5.0.12, the default value of this option
is the DEFAULT_PAGER setting in shorewallrc.
PATH=pathname[:pathname]...
Determines the order in which Shorewall6 searches directories for
executable files.
PERL=pathname
Added in Shorewall 4.4.11 RC1. Specifies the path name of the Perl
executable. Default is /usr/bin/perl. If the pathname specified by
this option does not exist or the named file is not executable,
then Shorewall6 falls back to /usr/bin/perl
PROVIDER_BITS=[number]
Added in Shorewall 4.4.26. The number of bits in the 32-bit packet
mark to be used for provider numbers. May be zero. See MASK_BITS
above for default value.
PROVIDER_OFFSET=[number]
Added in Shorewall 4.4.26. The offset from the right (low-order
end) of the provider number field in the 32-bit packet mark. If
non-zero, must be >= TC_BITS (Shorewall automatically adjusts
PROVIDER_OFFSET's value). PROVIDER_OFFSET + PROVIDER_BITS +
ZONE_BITS must be < 32. See MASK_BITS above for default value.
RCP_COMMAND="command"
RSH_COMMAND="command"
Earlier generations of Shorewall6 Lite required that remote root
login via ssh be enabled in order to use the load and reload
commands. Beginning with release 3.9.5, you may define an
alternative means for accessing the remote firewall system. In that
release, two new options were added to shorewall6.conf:.RS 4
RSH_COMMAND
RCP_COMMAND
The default values for these are as follows:.RS 4 RSH_COMMAND: ssh
${root}@${system} ${command}
RCP_COMMAND: scp ${files}
${root}@${system}:${destination}
Shell variables that will be set when the commands are invoked are as
follows:.RS 4 root - root user. Normally
root but may be overridden using the '-r'
option.
system - The name/IP address
of the remote firewall system.
command - For RSH_COMMAND,
the command to be executed on the firewall system.
files - For RCP_COMMAND, a
space-separated list of files to be copied to the
remote
firewall system.
destination - The directory
on the remote system that the files are to be copied
into.
RELATED_DISPOSITION=[ACCEPT|A_ACCEPT|A_DROP|A_REJECT|DROP|REJECT|CONTINUE]
Added in Shorewall 4.4.27. Shorewall has traditionally ACCEPTed
RELATED packets that don't match any rule in the RELATED section of
shorewall6-rules[6] (5). Concern about the safety of this practice
resulted in the addition of this option. When a packet in RELATED
state fails to match any rule in the RELATED section, the packet is
disposed of based on this setting. The default value is ACCEPT for
compatibility with earlier versions.
RELATED_LOG_LEVEL=log-level[:log-tag]
Added in Shorewall 4.4.27. Packets in the related state that do not
match any rule in the RELATED section of shorewall6-rules[6] (5)
are logged at this level. The default value is empty which means no
logging is performed.
REJECT_ACTION=action
Added in Shorewall 4.5.21. When a REJECT target is specified,
Shorewall normally handles the response as follows:
* If the destination address of the packet is a broadcast or
multicast address, the packet is dropped.
* if the protocol is ICMP (58) then the packet is dropped.
* if the protocol is TCP (6) then the packet is rejected with an
RST.
* if the protocol is UDP (17) then the packet is rejected with an
'port-unreachable' ICMP (ICMP6).
* if the protocol is ICMP (1) then the packet is rejected with a
'addr-unreachable' ICMP.
* otherwise, the packet is rejected with a 'adm-prohibited' ICMP.
You can modify this behavior by implementing your own action that
handles REJECT and specifying it's name in this option. The nolog
and inline options will automatically be assumed for the specified
action.
The following action implements the standard behavior:
?format 2
#TARGET SOURCE DEST PROTO
Broadcast(DROP) - - -
DROP - - 2
INLINE - - 6 ;; -j REJECT --reject-with tcp-reset
?if __ENHANCED_REJECT
INLINE - - 17 ;; -j REJECT
?if __IPV4
INLINE - - 1 ;; -j REJECT --reject-with icmp-host-unreachable
INLINE - - - ;; -j REJECT --reject-with icmp-host-prohibited
?else
INLINE - - 58 ;; -j REJECT --reject-with icmp6-addr-unreachable
INLINE - - - ;; -j REJECT --reject-with icmp6-adm-prohibited
?endif
?else
INLINE - - - ;; -j REJECT
?endif
REQUIRE_INTERFACE=[Yes|No]
Added in Shorewall 4.4.10. The default is No. If set to Yes, at
least one optional interface must be up in order for the firewall
to be in the started state. Intended to be used with the Shorewall
Init Package[21].
RESTART=[restart|reload]
Added in Shorewall 5.0.1 to replace LEGACY_RESTART which was added
in Shorewall 5.0.0. In that release, the reload command was
redefined to do what restart had done in earlier releases and
restart became a true restart (equivalent to stop followed by
start). When RESTART=reload, the restart command performs the same
operation as the reload command making it compatible with earlier
releases. If not specified, RESTART=reload is assumed.
RESTORE_ROUTEMARKS=[Yes|No]
Added in Shorewall 4.5.9. When set to Yes (the default), provider
marks are restored unconditionally at the top of the mangle OUTPUT
and PREROUTING chains, even if the saved mark is zero. When this
option is set to No, the mark is restored only if it is non-zero.
If you have problems with IPSEC ESP packets not being routed
correctly on output, try setting this option to No.
RESTOREFILE=filename
Specifies the simple name of a file in /var/lib/shorewall6 to be
used as the default restore script in the shorewall6 save,
shorewall6 restore, shorewall6 forget and shorewall6 -f start
commands.
RPFILTER_DISPOSITION=[DROP|REJECT|A_DROP|A_REJECT]
Added in Shorewall 4.5.7. Determines the disposition of packets
entering from interfaces with the rpfilter option (see
shorewall6-interfaces[22](5)). Packets disposed of by this option
are those whose response packets would not be sent through the same
interface receiving the packet.
RPFILTER_LOG_LEVEL=log-level[:log-tag]
Added in shorewall 4.5.7. Determines the logging of packets
disposed via the RPFILTER_DISPOSITION. The default value is info.
SAVE_IPSETS={Yes|No|setlist}
Re-enabled in Shorewall 4.4.6. If SAVE_IPSETS=Yes, then the current
contents of your ipsets will be saved by the shorewall stop and
shorewall save commands and restored by the shorewall start and
shorewall restore commands.
Beginning with Shorewall 4.6.4, you can restrict the set of ipsets
saved by specifying a setlist (a comma-separated list of ipv6 ipset
names).
SHOREWALL_SHELL=[pathname]
This option is used to specify the shell program to be used to
interpret the compiled script. If not specified or specified as a
null value, /bin/sh is assumed. Using a light-weight shell such as
ash or dash can significantly improve performance.
SMURF_DISPOSITION=[DROP|A_DROP]
Added in Shorewall 4.4.20. The default setting is DROP which causes
smurf packets (see the nosmurfs option in
shorewall6-interfaces[22](5)) to be dropped. A_DROP causes the
packets to be audited prior to being dropped and requires
AUDIT_TARGET support in the kernel and ip6tables.
SMURF_LOG_LEVEL=[log-level[:log-tag]]
Specifies the logging level for smurf packets (see the nosmurfs
option in shorewall6-interfaces[22](5)). If set to the empty value
( SMURF_LOG_LEVEL="" ) then smurfs are not logged.
SFILTER_DISPOSITION=[DROP|REJECT|A_DROP|A_REJECT]
Added in Shorewall 4.4.20. Determines the disposition of packets
matching the sfilter option (see shorewall6-interfaces[22](5)) and
of hairpin packets on interfaces without the routeback option.[23]
interfaces without the routeback option.
SFILTER_LOG_LEVEL=log-level[:log-tag]
Added on Shorewall 4.4.20. Determines the logging of packets
matching the sfilter option (see shorewall6-interfaces[22](5)) and
of hairpin packets on interfaces without the routeback option.[24]
interfaces without the routeback option. The default is info. If
you don't wish for these packets to be logged, use
SFILTER_LOG_LEVEL=none.
STARTUP_ENABLED={Yes|No}
Determines if Shorewall6 is allowed to start. As released from
shorewall.net, this option is set to No. When set to Yes or yes,
Shorewall6 may be started. Used as a guard against Shorewall6 being
accidentally started before it has been configured.
STARTUP_LOG=[pathname]
If specified, determines where Shorewall will log the details of
each start, reload, restart, refresh, try, and safe-* command.
Logging verbosity is determined by the setting of LOG_VERBOSITY
above.
SUBSYSLOCK=[pathname]
This parameter should be set to the name of a file that the
firewall should create if it starts successfully and remove when it
stops. Creating and removing this file allows Shorewall6 to work
with your distribution's initscripts. For RedHat, this should be
set to /var/lock/subsys/shorewall6. For Debian, the value is
/var/lock/shorewall6 and in LEAF it is /var/run/shorewall.
TC=[pathname]
If specified, gives the pathname of the 'tc' executable. If not
specified, 'tc' is assumed and the utility will be located using
the current PATH setting.
TC_BITS=[number]
Added in Shorewall 4.4.26. The number of bits at the low end of the
32-bit packet mark to be used for traffic shaping marking. May be
zero. See MASK_BITS above for default value.
TC_ENABLED=[Yes|No|Internal|Simple|Shared]
If you say Yes or yes here, Shorewall6 will use a script that you
supply to configure traffic shaping. The script must be named
'tcstart' and must be placed in a directory on your CONFIG_PATH.
If you say No or no then traffic shaping is not enabled.
If you set TC_ENABLED=Internal or internal or leave the option
empty then Shorewall6 will use its builtin traffic shaper
(tc4shorewall6 written by Arne Bernin.
If you set TC_ENABLED=Simple (Shorewall 4.4.6 and later), simple
traffic shaping using shorewall-tcinterfaces[25](5) and
shorewall-tcpri[26](5) is enabled.
Beginning with Shorewall 4.4.15, if you set TC_ENABLED=Shared or
shared, then you should create symbolic links from your Shorewall6
configuration directory (normally /etc/shorewall6/) to your
Shorewall tcdevices and tcclasses files. This allows the compiler
to have access to your Shorewall traffic shaping configuration so
that it can validate CLASSIFY rules in shorewall6-tcrules[9] (5).
Warning
If you also run Shorewall and if you have TC_ENABLED=Internal
in your shorewall-conf[10](5), then you will want TC_ENABLED=No
or TC_ENABLED=Shared in this file.
TC_EXPERT={Yes|No}
Normally, Shorewall6 tries to protect users from themselves by
preventing PREROUTING and OUTPUT tcrules from being applied to
packets that have been marked by the 'track' option in
shorewall6-providers[27](5).
If you know what you are doing, you can set TC_EXPERT=Yes and
Shorewall6 will not include these cautionary checks.
TC_PRIOMAP=map
Added in Shorewall 4.4.6. Determines the mapping of a packet's TOS
field to priority bands. See shorewall6-tcpri[28](5). The map
consists of 16 space-separated digits with values 1, 2 or 3. A
value of 1 corresponds to Linux priority 0, 2 to Linux priority 1,
and 3 to Linux Priority 2. The first entry gives the priority of
TOS value 0, the second of TOS value 1, and so on. See tc-prio(8)
for additional information.
The default setting is TC_PRIOMAP="2 3 3 3 2 3 1 1 2 2 2 2 2 2 2
2".
TCP_FLAGS_DISPOSITION=[ACCEPT|DROP|REJECT]
Determines the disposition of TCP packets that fail the checks
enabled by the tcpflags interface option (see
shorewall6-interfaces[22](5)) and must have a value of ACCEPT
(accept the packet), REJECT (send an RST response) or DROP (ignore
the packet). If not set or if set to the empty value (e.g.,
TCP_FLAGS_DISPOSITION="") then TCP_FLAGS_DISPOSITION=DROP is
assumed.
TCP_FLAGS_LOG_LEVEL=[log-level[:log-tag]]
Determines the syslog level for logging packets that fail the
checks enabled by the tcpflags interface option. The value must be
a valid syslogd log level. If you don't want to log these packets,
set to the empty value (e.g., TCP_FLAGS_LOG_LEVEL="").
TRACK_PROVIDERS={Yes|No}
Added in Shorewall 4.4.3. When set to Yes, causes the track option
to be assumed on all providers defined in
shorewall6-providers[27](5). May be overridden on an individual
provider through use of the notrack option. The default value is
'No'.
Beginning in Shorewall 4.4.6, setting this option to 'Yes' also
simplifies PREROUTING rules in shorewall6-tcrules[9](5).
Previously, when TC_EXPERT=No, packets arriving through 'tracked'
provider interfaces were unconditionally passed to the PREROUTING
tcrules. This was done so that tcrules could reset the packet mark
to zero, thus allowing the packet to be routed using the 'main'
routing table. Using the main table allowed dynamic routes (such as
those added for VPNs) to be effective. The
shorewall6-rtrules[29](5) file was created to provide a better
alternative to clearing the packet mark. As a consequence, passing
these packets to PREROUTING complicates things without providing
any real benefit. Beginning with Shorewall 4.4.6, when
TRACK_PROVIDERS=Yes and TC_EXPERT=No, packets arriving through
'tracked' interfaces will not be passed to the PREROUTING rules.
Since TRACK_PROVIDERS was just introduced in 4.4.3, this change
should be transparent to most, if not all, users.
TRACK_RULES={Yes|No|File}
Added in Shorewall 4.5.20. If set to Yes, causes the compiler to
add a comment to iptables rules to indicate the file name and line
number of the configuration entry that generated the rule. If set
to No (the default), then no such comments are added.
Setting this option to Yes requires the Comments capability in
iptables and kernel.
Beginning with Shorewall 5.0.5, the option may also be set to File.
That setting causes similar comments to be added to the
.ip6tables-restore-input file, which is normally created in
/var/lib/shorewall6.
UNTRACKED_DISPOSITION=[ACCEPT|A_ACCEPT|A_DROP|A_REJECT|DROP|REJECT|CONTINUE]
Added in Shorewall 4.5.13. Shorewall has traditionally passed
UNTRACKED packets through the NEW section of shorewall6-rules[6]
(5). When a packet in UNTRACKED state fails to match any rule in
the UNTRACKED section, the packet is disposed of based on this
setting. The default value is CONTINUE for compatibility with
earlier versions.
UNTRACKED_LOG_LEVEL=log-level[:log-tag]
Added in Shorewall 4.5.13. Packets in the UNTRACKED state that do
not match any rule in the UNTRACKED section of shorewall6-rules[6]
(5) are logged at this level. The default value is empty which
means no logging is performed.
USE_DEFAULT_RT=[Yes|No]
Added in Shorewall6 4.4.25. When set to 'Yes', this option causes
the Shorewall6 multi-ISP feature to create a set of routing rules
which are resilient to changes in the main routing table. Such
changes can occur for a number of reasons, VPNs going up and down
being an example. The idea is to send packets through the main
table prior to applying any of the Shorewall6-generated routing
rules. So changes to the main table will affect the routing of
packets by default.
When USE_DEFAULT_RT=Yes:
1. Both the DUPLICATE and the COPY columns in
shorewall6-providers[27](5) file must remain empty (or contain
"-").
2. The default route is added to the the 'default' table rather
than to the main table.
3. balance is assumed unless loose is specified.
4. Packets are sent through the main routing table by a rule with
priority 999. In shorewall6-routing_rules[30](5), the range
1-998 may be used for inserting rules that bypass the main
table.
5. All provider gateways must be specified explicitly in the
GATEWAY column. detect may not be specified.
6. You should disable all default route management outside of
Shorewall6. If a default route is added to the main table while
Shorewall is started, then all policy routing will stop working
(except for those routing rules in the priority range 1-998).
Prior to Shorewall 4.6.0, if USE_DEFAULT_RT was not set or if it
was set to the empty string then USE_DEFAULT_RT=No was assumed.
Beginning with Shorewall 4.6.0, the default is USE_DEFAULT_RT=Yes
and use of USE_DEFAULT_RT=No is deprecated.
Warning
The enable, disable and reenable commands do not work correctly
when USE_DEFAULT_RT=No.
USE_PHYSICAL_NAMES=[Yes|No]
Added in Shorewall 4.4.27. Normally, when Shorewall creates a
Netfilter chain that relates to an interface, it uses the
interface's logical name as the base of the chain name. For
example, if the logical name for an interface is OAKLAND, then the
input chain for traffic arriving on that interface would be
'OAKLAND_in'. If this option is set to Yes, then the physical name
of the interface will be used the base of the chain name.
USE_RT_NAMES=[Yes|No]
Added in Shorewall 4.5.15. When set to 'Yes', Shorewall will use
routing table (provider) names in the generated script rather than
table numbers. When set to 'No' (the default), routing table
numbers will be used.
Caution
If you set USE_RT_NAMES=Yes and KEEP_RT_TABLES=Yes, then you
must insure that all of your providers have entries in
/etc/iproute2/rt_tables as well as the following entries:
255 local
254 main
253 default
250 balance
0 unspec
Without these entries, the firewall will fail to start.
VERBOSE_MESSAGES=[Yes|No]
Added in Shorewall 5.0.9. When Yes (the default), messages produced
by the ?INFO and ?WARNING directives include the filename and
linenumber of the directive. When set to No, that additional
information is omitted. The setting may be overridden on a
directive by directive basis by following ?INFO or ?WARNING with
'!' (no intervening white space).
VERBOSITY=[number]
Shorewall6 has traditionally been very noisy (produced lots of
output). You may set the default level of verbosity using the
VERBOSITY OPTION.
Values are:
0 - Silent. You may make it more verbose using the -v
option
1 - Major progress messages displayed
2 - All progress messages displayed (pre Shorewall6-3.2.0
behavior)
If not specified, then 2 is assumed.
WARNOLDCAPVERSION=[Yes|No]
Added in Shorewall 4.5.12. When set to Yes (the default), the
compiler issues a warning when it finds a capabilities file that
doesn't specify all of the capabilities supported by the compiler.
When WARNOLDCAPVERSION is set to No, no warning is issued.
WIDE_TC_MARKS=[Yes|No]
Deprecated in Shorewall 4.4.26 in favor of TC_BITS and MASK_BITS.
When set to No (the default), traffic shaping marks are 8 bytes
wide (possible values are 1-255). When WIDE_TC_MARKS=Yes, traffic
shaping marks are 14 bytes wide (values 1-16383). The setting of
WIDE_TC_MARKS also has an effect on the HIGH_ROUTE_MARKS option
(see above).
WORKAROUNDS=[Yes|No]
Added in Shorewall 4.6.11. Over time, there have been a number of
changes in Shorewall that work around defects in other products
such as iptables and ipset. When WORKAROUNDS=Yes, these workarounds
are enabled; when WORKAROUNDS=No, they are disabled. If not
specified or if specified as empty, WORKAROUNDS=Yes is assumed.
Warning
Do not set WORKAROUNDS=Yes if you need to be able to use
Shorewall-generated scripts (such as created by the save
command) built by Shorewall 4.4.7 or older.
ZERO_MARKS=[Yes|No]
Added in Shorewall 5.0.12, this is a workaround for an issue where
packet marks are not zeroed by the kernel. It should be set to No
(the default) unless you find that incoming packets are being
mis-routed for no apparent reasons.
Caution
Do not set this option to Yes if you have IPSEC software
running on the firewall system.
ZONE_BITS=[number]
Added in Shorewall 4.4.26. When non-zero, enables automatic packet
marking by source zone and determines the number of bits in the
32-bit packet mark to be used for the zone mark. Default value is
0.
ZONE2ZONE={2|-}
Added in Shorewall 4.4.4. This option determines how Shorewall
constructs chain names involving zone names and/or 'all'. Beginning
with Shorewall 4.6.0, the default is '-' (e.g., fw-net); prior to
that release, the default was '2' (e.g., fw2net).
FILES
/etc/shorewall6/shorewall6.conf
SEE ALSO
shorewall6(8), shorewall6-accounting(5), shorewall6-actions(5), shorewall6-blacklist(5), shorewall6-hosts(5), shorewall6-interfaces(5), shorewall6-ipsec(5), shorewall6-maclist(5), shorewall6-masq(5), shorewall6-nat(5), shorewall6-netmap(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-tcclasses(5), shorewall6-tcdevices(5), shorewall6-tcrules(5), shorewall6-tos(5), shorewall6-tunnels(5), shorewall6-zones(5)
NOTES
1. shorewall6-policy
http://www.shorewall.net/manpages6/shorewall6-policy.html
2. shorewall6-accounting
http://www.shorewall.net/manpages6/shorewall6-accounting.html
3. shorewall-routestopped
http://www.shorewall.netshorewall-routestopped.html
4. shorewall-stoppedrules
http://www.shorewall.netshorewall-stoppedrules.html
5. shorewall6-conntrack
http://www.shorewall.net/manpages6/shorewall6-conntrack.html
6. shorewall6-rules
http://www.shorewall.net/manpages6/shorewall6-rules.html
7. shorewall6-tcfilters(5)
http://www.shorewall.netshorewall6-tcfilters.html
8. shorewall6-blrules
http://www.shorewall.net/manpages6/shorewall6-blrules.html
9. shorewall6-tcrules
http://www.shorewall.net/manpages6/shorewall6-tcrules.html
10. shorewall-conf
http://www.shorewall.net/manpages/shorewall.conf.html
11. http://www.shorewall.net/ISO-3661.html
http://www.shorewall.net/ISO-3661.html
12. shorewall6-zones
http://www.shorewall.net/manpages6/shorewall6-zones.html
13. shorewall6-nesting
http://www.shorewall.net/manpages6/shorewall6-nesting.html
14. alternative specificaitons
http://www.shorewall.net/configuration_file_basics.htm#Pairs
15. shorewall6-masq(5)
http://www.shorewall.netshorewall-masq.html
16. shorewall6-mangle(5
http://www.shorewall.netshorewall6-mangle.html
17. shorewall6(8)
http://www.shorewall.netmanpages6/shorewall6.html
18. shorewall6-maclist
http://www.shorewall.net/manpages6/shorewall6-maclist.html
19. shorewall6.conf
http://www.shorewall.net/manpages6/shorewall6.conf.html
20. the complete matrix of host groups defined by the zones, interfaces
and hosts files
http://www.shorewall.net/ScalabilityAndPerformance.html
21. Shorewall Init Package
http://www.shorewall.net/manpages/shorewall-init.html
22. shorewall6-interfaces
http://www.shorewall.net/manpages6/shorewall6-interfaces.html
23. Hairpin packets are packets that are routed out of the same
interface that they arrived on.
24. Hairpin packets are packets that are routed out of the same
interface that they arrived on.
25. shorewall-tcinterfaces
http://www.shorewall.net/manpages/shorewall-tcinterfaces.html
26. shorewall-tcpri
http://www.shorewall.net/manpages/shorewall-tcpri.html
27. shorewall6-providers
http://www.shorewall.net/manpages6/shorewall6-providers.html
28. shorewall6-tcpri
http://www.shorewall.net/manpages6/shorewall6-tcpri.html
29. shorewall6-rtrules
http://www.shorewall.net/manpages6/shorewall6-rtrules.html
30. shorewall6-routing_rules
http://www.shorewall.net/manpages6/shorewall6-routing_rules.html
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