shorewall.conf5shorewall.confShorewall global configuration file/etc/shorewall/shorewall.confDescriptionThis file sets options that apply to Shorewall as a whole.The file consists of Shell comments (lines beginning with '#'),
blank lines and assignment statements
(variable=value).OPTIONSMany 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 Shorewall also uses that term.Valid levels are: 7 debug
6 info
5 notice
4 warning
3 err
2 crit
1 alert
0 emergFor most Shorewall logging, a level of 6 (info) is appropriate.
Shorewall log messages are generated by NetFilter and are logged using
facility 'kern' and the level that you specifify. 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 ULOG target support, you may also
specify a log level of ULOG (must be all caps). Rather than log its
messages to syslogd, Shorewall will direct netfilter to log the messages
via the ULOG 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 Shorewall message to their own log
fileThe following options may be set in shorewall.conf.ACCEPT_DEFAULT={action|macro|none}DROP_DEFAULT={action|macro|none}REJECT_DEFAULT={action|macro|none}QUEUE_DEFAULT={action|macro|none}NFQUEUE_DEFAULT={action|macro|none} (Shorewall-perl 4.0.3 and later)In earlier Shorewall versions, a "default action" for DROP and
REJECT policies was specified in the file
/usr/share/shorewall/actions.std.To allow for default rules to be applied when USE_ACTIONS=No,
the DROP_DEFAULT, REJECT_DEFAULT, ACCEPT_DEFAULT, QUEUE_DEFAULT and
NFQUEUE_DEFAULT options have been added.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.b) The name of a macro
(Shorewall-shell only)c) None or noneThe default values are:DROP_DEFAULT="Drop"REJECT_DEFAULT="Reject"ACCEPT_DEFAULT="none"QUEUE_DEFAULT="none"NFQUEUE_DEFAULT="None"If USE_ACTIONS=Yes, then these values refer to action.Drop and
action.Reject respectively. If USE_ACTIONS=No, then these values
refer to macro.Drop and macro.Reject.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 shorewall-policy(5).ADD_IP_ALIASES=[Yes|No]This parameter determines whether Shorewall automatically adds
the external address(es) in shorewall-nat(5). If the variable
is set to Yes or yes then Shorewall automatically adds these
aliases. If it is set to No or
no, you must add these aliases
yourself using your distribution's network configuration
tools.If this variable is not set or is given an empty value
(ADD_IP_ALIASES="") then ADD_IP_ALIASES=Yes is assumed.Addresses added by ADD_IP_ALIASES=Yes are deleted and
re-added during shorewall restart. As a consequence, connections
using those addresses may be severed.ADD_SNAT_ALIASES=[Yes|No]This parameter determines whether Shorewall automatically adds
the SNAT ADDRESS in shorewall-masq(5). If the variable
is set to Yes or yes then Shorewall automatically adds these
addresses. If it is set to No or
no, you must add these addresses
yourself using your distribution's network configuration
tools.If this variable is not set or is given an empty value
(ADD_SNAT_ALIASES="") then ADD_SNAT_ALIASES=No is assumed.Addresses added by ADD_SNAT_ALIASES=Yes are deleted and
re-added during shorewall restart. As a consequence, connections
using those addresses may be severed.ADMINISABSENTMINDED=[Yes|No]The value of this variable affects Shorewall's stopped state.
When ADMINISABSENTMINDED=No, only traffic to/from those addresses
listed in shorewall-routestopped(5)
is accepted when Shorewall is stopped. When ADMINISABSENTMINDED=Yes,
in addition to traffic to/from addresses in shorewall-routestopped(5),
connections that were active when Shorewall stopped continue to work
and all new connections from the firewall system itself are allowed.
If this variable is not set or is given the empty value then
ADMINISABSENTMINDED=No is assumed.BIGDPORTLISTS=[Yes|No]Setting this option to 'Yes' allows you to include arbitrarily
long destination port lists in all configuration files.BLACKLIST_DISPOSITION=[DROP|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.BLACKLIST_LOGLEVEL=[log-level]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_LOGLEVEL=debug). If you do not assign a value or if you
assign an empty value then packets from blacklisted hosts are not
logged.BLACKLISTNEWONLY={Yes|No}When set to Yes or yes, blacklists are only consulted for new
connections. When set to No or
no, blacklists are consulted for
every packet (will slow down your firewall noticably if you have
large blacklists). If the BLACKLISTNEWONLY option is not set or is
set to the empty value then BLACKLISTNEWONLY=No is assumed.BLACKLISTNEWONLY=No is incompatible with
FASTACCEPT=Yes.BRIDGING={Yes|No}When set to Yes or yes, enables Shorewall Bridging
support.BRIDGING=Yes may not work properly with Linux kernel
2.6.20 or later and is not supported by Shorewall-perl.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 Shorewall won't clear the current traffic control rules during
[re]start. 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/shorewall/tcstart file. That way, your traffic shaping rules
can still use the “fwmark” classifier based on packet marking
defined in shorewall-tcrules(5). If not
specified, CLEAR_TC=Yes is assumed.CONFIG_PATH=[directory[:directory]...]Specifies where configuration files other than shorewall.conf
may be found. CONFIG_PATH is specifies as a list of directory names
separated by colons (":"). When looking for a configuration file
other than shorewall.conf:If the command is "try" or if "-c <configuration
directory>" was specified in the command 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/shorewall/configpath are
used. As released from shorewall.net, that file sets the
CONFIG_PATH to /etc/shorewall:/usr/share/shorewall but your
particular distribution may set it differently. See the output of
shorewall show config for the default on your system.Note that the setting in /usr/share/shorewall/configpath is
always used to locate shorewall.conf.
DELAYBLACKLISTLOAD={Yes|No}Users with a large static black list (shorewall-blacklist(5)) may
want to set the DELAYBLACKLISTLOAD option to Yes. When DELAYBLACKLISTLOAD=Yes, Shorewall
will enable new connections before loading the blacklist rules.
While this may allow connections from blacklisted hosts to slip by
during construction of the blacklist, it can substantially reduce
the time that all new connections are disabled during shorewall [re]start.DELAYBLACKLISTLOAD=Yes is not supported by
Shorewall-perl.DELETE_THEN_ADD={Yes|No}Added in Shorewall 4.0.4. If set to Yes (the default value),
entries in the /etc/shorewall/route_stopped files 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.DETECT_DNAT_IPADDRS=[Yes|No]If set to Yes or yes, Shorewall will detect the first IP
address of the interface to the source zone and will include this
address in DNAT rules as the original destination IP address. If set
to No or no, Shorewall will not detect this address
and any destination IP address will match the DNAT rule. If not
specified or empty, “DETECT_DNAT_IPADDRS=Yes” is assumed.DONT_LOAD=[module[,module]...]Added in Shorewall-4.0.6. Causes Shorewall to not load the
listed modules.DYNAMIC_ZONES={Yes|No}When set to Yes or yes, enables dynamic zones. DYNAMIC_ZONES=Yes
is not allowed in configurations that will run under Shorewall
Lite.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 infothen the chain name is 'net2all'
which is also the chain named in Shorewall log messages generated as
a result of the policy. If EXPAND_POLICIES=Yes, then Shorewall-perl
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.EXPORTPARAMS={Yes|No}It is quite difficult to code a 'params' file that assigns
other than constant values such that it works correctly with
Shorewall Lite. The EXPORTPARAMS option works around this problem.
When EXPORTPARAMS=No, the 'params' file is not copied to the
compiler output.With EXPORTPARAMS=No, if you need to set environmental
variables on the firewall system for use by your extension scripts,
then do so in the init extension script.The default is EXPORTPARAMS=YesFASTACCEPT={Yes|No}Normally, Shorewall 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
'loc2net' chain.If you set FASTACCEPT=Yes, then ESTABLISHED/RELEATED 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 shorewall-rules(5).FASTACCEPT=Yes is incompatible with
BLACKLISTNEWONLY=No.HIGH_ROUTE_MARKS={Yes|No}Prior to version 3.2.0, it was not possible to use connection
marking in shorewall-tcrules(5) if you
have a multi-ISP configuration that uses the track option.Beginning with release 3.2.0, you may now set
HIGH_ROUTE_MARKS=Yes in to effectively divide the packet mark and
connection mark into two 8-byte mark fields.When you do this:The MARK field in the providers file must have a value
that is less than 65536 and that is a multiple of 256 (using hex
representation, the values are 0x0100-0xFF00 with the low-order
8 bits being zero).You may only set those mark values in the PREROUTING
chain.Marks used for traffic shaping must still be in the range
of 1-255 and may still not be set in the PREROUTING
chain.When you SAVE or RESTORE in tcrules, only the TC mark
value is saved or restored. Shorewall handles saving and
restoring the routing (provider) marks.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 shorewall-zones(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
shorewall-nesting(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).IP_FORWARDING=[On|Off|Keep]This parameter determines whether Shorewall enables or
disables IPV4 Packet Forwarding (/proc/sys/net/ipv4/ip_forward).
Possible values are:On or onpacket forwarding will be enabled.Off or offpacket forwarding will be disabled.Keep or keepShorewall 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.
IPSECFILE={zones|ipsec}This should be set to zones
for all new Shorewall installations. IPSECFILE=ipsec is only used
for compatibility with pre-Shorewall-3.0 configurations.IPTABLES=[pathname]This parameter names the iptables executable to be used by
Shorewall. If not specified or if specified as a null value, then
the iptables executable located using the PATH option is
used.Regardless of how the IPTABLES utility is located (specified
via IPTABLES= or located via PATH), Shorewall uses the
iptables-restore and iptables-save utilities from that same
directory.KEEP_RT_TABLES={Yes|No}Added in Shorewall 4.0.3. When set to ,
this option prevents scripts generated by Shorewall-perl from
altering the /etc/iproute2/rt_tables database when there are entries
in /etc/shorewall/providers. If you set this
option to while Shorewall (Shorewall-lite) is
running, you should remove the file
/var/lib/shorewall/rt_tables
(/var/lib/shorewall-lite/rt_tables) before your
next stop, refresh,
restore on restart
command.The default is KEEP_RT_TABLES=No.LOG_MARTIANS=[Yes|No|Keep]If set to Yes or yes, sets
/proc/sys/net/ipv4/conf/all/log_martians and
/proc/sys/net/ipv4/conf/default/log_martians to 1. Default is
No which sets both of the above to
zero. If you do not enable martian logging for all interfaces, you
may still enable it for individual interfaces using the logmartians interface option in shorewall-interfaces(5).The value Keep is only
allowed under Shorewall-perl. It causes Shorewall to ignore the
option. If the option is set to Yes, then martians are logged on all
interfaces. If the option is set to No, then martian logging is disabled on all
interfaces except those specified in shorewall-interfaces(5).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 disabled0 — Silent. Only error messages are logged.1 — Major progress messages logged.2 — All progress messages loggedIf 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 Shorewall 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
To help insure that all packets in the NEW state are
logged, rate limiting (LOGBURST and 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.Do not use this option if the resulting log messages will
be sent to another system.
LOGFILE=[pathname]This parameter tells the /sbin/shorewall program where to look
for Shorewall 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.LOGFORMAT=["formattemplate"]The value of this variable generate the --log-prefix setting
for Shorewall 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
“Shorewall:%s:%s:” is assumed.LOGBURST=[burst]LOGRATE=[rate/{minute|second}]These parameters set the match rate and initial burst size for
logged packets. Please see iptables(8) for a description of the
behavior of these parameters (the iptables option --limit is set by
LOGRATE and --limit-burst is set by LOGBURST). If both parameters
are set empty, no rate-limiting will occur.Example: LOGRATE=10/minute
LOGBURST=5For each logging rule, the first time the rule is reached, the
packet will be logged; in fact, since the burst is 5, the first five
packets will be logged. After this, it will be 6 seconds (1 minute
divided by the rate of 10) before a message will be logged from the
rule, regardless of how many packets reach it. Also, every 6 seconds
which passes without matching a packet, one of the bursts will be
regained; if no packets hit the rule for 30 seconds, the burst will
be fully recharged; back where we started.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.MACLIST_DISPOSITION=[ACCEPT|DROP|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.MACLIST_LOG_LEVEL=[log-level]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 shorewall-maclist(5) can be
improved by setting the MACLIST_TTL variable in shorewall.conf(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
shorewall-maclist(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).MAPOLDACTIONS=[Yes|No]Previously, Shorewall included a large number of standard
actions (AllowPing, AllowFTP, ...). These have been replaced with
parameterized macros. For compatibility, Shorewall can map the old
names into invocations of the new macros if you set
MAPOLDACTIONS=Yes. If this option is not set or is set to the empty
value (MAPOLDACTIONS="") then MAPOLDACTIONS=Yes is assumed.MAPOLDACTIONS=Yes is not supported by Shorewall-perl. With
Shorewall-perl, if MAPOLDACTIONS is not set or is set to the ampty
value then MAPOLDACTIONS=No is assumed.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 /sbin/shorewall 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.MODULE_SUFFIX=["extension ..."]The value of this option determines the possible file
extensions of kernel modules. The default value is "o gz ko
o.gz".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
-r`/kernel/net/ipv4/netfilter" in versions of Shorewall prior to
3.2.4 and "/lib/modules/`uname
-r`/kernel/net/ipv4/netfilter:/lib/modules/`uname
-r`/kernel/net/ipv4/netfilter" in later versions.MULTICAST=[Yes|No]This option will normally be set to 'No' (the default). It
should be set to 'Yes' under the following circumstances:You have an interface that has parallel zones defined via
/etc/shorewall/hosts.You want to forward multicast packets to two or more of
those parallel zones.In such cases, you will configure a
network on each zone receiving multicasts.The MULTICAST option is only recognized by Shorewall-perl and
is ignored by Shorewall-shell.MUTEX_TIMEOUT=[seconds]The value of this variable determines the number of seconds
that programs will wait for exclusive access to the Shorewall 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
shorewall restart command.OPTIMIZE=[0|1]Traditionally, Shorewall has created rules for the complete matrix of host
groups defined by the zones, interfaces and hosts files. 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
OPTIMIZE=1.The OPTIMIZE 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.PATH=pathname[:pathname]...Determines the order in which Shorewall searches directories
for executable files.PKTTYPE={Yes|No}Normally Shorewall attempts to use the iptables packet type
match extension to determine broadcast and multicast packets.This can cause a message to appear during shorewall start
(modprobe: cant locate module ipt_pkttype).Some users have found problems with the packet match
extension with the result that their firewall log is flooded
with messages relating to broadcast packets.
If you are experiencing either of these problems, setting
PKTTYPE=No will prevent Shorewall from trying to use the packet
type match extension and to use IP address matching to determine
which packets are broadcasts or multicasts.
RCP_COMMAND="command"RSH_COMMAND="command"Eariler generations of Shorewall 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 shorewall.conf:RSH_COMMANDRCP_COMMANDThe default values for these are as
follows:RSH_COMMAND: ssh ${root}@${system} ${command}RCP_COMMAND: scp ${files}
${root}@${system}:${destination}Shell variables that will be set when the commands
are envoked are as follows:root - root user. Normally
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.RESTOREFILE=filenameSpecifies the simple name of a file in /var/lib/shorewall to
be used as the default restore script in the shorewall save, shorewall restore, shorewall forget and shorewall -f start commands.RETAIN_ALIASES={Yes|No}During shorewall start, IP
addresses to be added as a consequence of ADD_IP_ALIASES=Yes and
ADD_SNAT_ALIASES=Yes are quietly deleted when shorewall-nat(5) and shorewall-masq(5) are processed
then are re-added later. This is done to help ensure that the
addresses can be added with the specified labels but can have the
undesirable side effect of causing routes to be quietly deleted.
When RETAIN_ALIASES is set to Yes, existing addresses will not be
deleted. Regardless of the setting of RETAIN_ALIASES, addresses
added during shorewall start are
still deleted at a subsequent shorewall
stop or shorewall
restart.RFC1918_LOG_LEVEL=[log-level]This parameter determines the level at which packets logged
under the norfc1918 mechanism are
logged. The value must be a valid syslog level and if no level is
given, then info is assumed.RFC1918_STRICT=[Yes|No]Traditionally, the RETURN target in the 'rfc1918' file has
caused norfc1918 processing to cease for a packet if the packet's
source IP address matches the rule. Thus, if you have this entry in
shorewall-rfc1918(5): #SUBNETS TARGET
192.168.1.0/24 RETURNthen traffic from 192.168.1.4 to 10.0.3.9 will be accepted
even though you also have: #SUBNETS TARGET
10.0.0.0/8 logdropSetting RFC1918_STRICT=Yes in shorewall.conf will cause such
traffic to be logged and dropped since while the packet's source
matches the RETURN rule, the packet's destination matches the
'logdrop' rule.If not specified or specified as empty (e.g.,
RFC1918_STRICT="") then RFC1918_STRICT=No is assumed.RFC1918_STRICT=Yes requires that your kernel and iptables
support 'Connection Tracking' match.ROUTE_FILTER=[Yes|No|Keep]If this parameter is given the value Yes or yes
then route filtering (anti-spoofing) is enabled on all network
interfaces which are brought up while Shorewall is in the started
state. The default value is no.The value Keep is only
allowed under Shorewall-perl. It causes Shorewall to ignore the
option. If the option is set to Yes, then route filtering occurs on all
interfaces. If the option is set to No, then route filtering is disabled on all
interfaces except those specified in shorewall-interfaces(5).SAVE_IPSETS={Yes|No}If SAVE_IPSETS=Yes, then the current contents of your ipsets
will be saved by the shorewall save
command. Regardless of the setting of SAVE_IPSETS, if saved ipset
contents are available then they will be restored by shorewall restore.SHOREWALL_COMPILER={perl|shell}Specifies the compiler to use to generate firewall scripts
when both compilers are installed. The value of this option can be
either or . If both
compilers are installed and SHOREWALL_SHELL is not set, then
SHOREWALL_SHELL=shell is assumed.If you add 'SHOREWALL_COMPILER=perl' to
/etc/shorewall/shorewall.conf then by default,
the Shorewall-perl compiler will be used on the system. If you add
it to shorewall.conf in a separate directory
(such as a Shorewall-lite export directory) then the Shorewall-perl
compiler will only be used when you compile from that
directory.If you only install one compiler, it is suggested that you do
not set SHOREWALL_COMPILER.This setting may be overriden in those commands that invoke
the compiler by using the -C command option (see shorewall(8)).SHOREWALL_SHELL=[pathname]This option is used to specify the shell program to be used to
run the Shorewall compiler and 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_LOG_LEVEL=[log-level]Specifies the logging level for smurf packets (see the
nosmurfs option in shorewall-interfaces(5)). If
set to the empty value ( SMURF_LOG_LEVEL="" ) then smurfs are not
logged.STARTUP_ENABLED={Yes|No}Determines if Shorewall is allowed to start. As released from
shorewall.net, this option is set to No. When set to Yes or yes,
Shorewall may be started. Used as a guard against Shorewall being
accidentally started before it has been configured.STARTUP_LOG=[pathname]If specified, determines where Shorewall will log the details
of each start, restart and refresh 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 Shorewall to work with
your distribution's initscripts. For RedHat, this should be set to
/var/lock/subsys/shorewall. For Debian, the value is
/var/state/shorewall and in LEAF it is /var/run/shorwall.TC_ENABLED=[Yes|No|Internal]If you say Yes or yes here, Shorewall 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 Shorewall will use its builtin traffic shaper
(tc4shorewall written by Arne Bernin.TC_EXPERT={Yes|No}Normally, Shorewall 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 shorewall-providers(5).If you know what you are doing, you can set TC_EXPERT=Yes and
Shorewall will not include these cautionary checks.TCP_FLAGS_DISPOSITION=[ACCEPT|DROP|REJECT]Determines the disposition of TCP packets that fail the checks
enabled by the tcpflags interface
option (see shorewall-interfaces(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]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="").USE_ACTIONS={Yes|No}While Shorewall Actions can be very useful, they also require
a sizable amount of code to implement. By setting USE_ACTIONS=No,
embedded Shorewall installations can omit the large library
/usr/share/shorewall/lib.actions.USE_ACTIONS=No is not supported by Shorewall-perl.VERBOSITY=[number]Shorewall 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
option1 — Major progress messages displayed2 — All progress messages displayed (pre Shorewall-3.2.0
behavior)If not specified, then 2 is assumed.FILES/etc/shorewall/shorewall.confSee ALSOshorewall(8), shorewall-accounting(5), shorewall-actions(5),
shorewall-blacklist(5), shorewall-hosts(5), shorewall-interfaces(5),
shorewall-ipsec(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-route_rules(5), shorewall-routestopped(5), shorewall-rules(5),
shorewall-tcclasses(5), shorewall-tcdevices(5), shorewall-tcrules(5),
shorewall-tos(5), shorewall-tunnels(5), shorewall-zones(5)