shorewall_code/Shorewall/releasenotes.txt

Shorewall 3.0.0 RC 3.

Problems Corrected in 3.0.0 RC 3:

1)  Shorewall no longer has any functionality that is dependent on the
    Netfilter ROUTE target and extended packet marking so detection and
    reporting of those capabilities has been removed.

2)  Previously, the following message could appear in the error output
    from the 'check' command:

    "/usr/share/shorewall/firewall:  line 128:  $RESTOREBASE:  ambiguous
    redirect"

3)  The test that Shorewall uses to detect the availability of the
    owner match capability has been changed to avoid the generation
    of ipt_owner messages under kernel 2.6.14. The affected configuration
    files have been updated to warn that +<program name> is not supported
    by kernel versions 2.6.14 and later.

4)  When MACLIST_TABLE=mangle and an interface is enabled for DHCP (the
    'dhcp' option is specified in /etc/shorewall/interfaces) then broadcasts
    on UDP port 67 to address 255.255.255.255 from address 0.0.0.0 were being
    dropped and logged. While this did not prevent the client from acquiring
    an IP address, it could result in lots of log messages.

Migration Considerations:

1) The "monitor" command has been eliminated.

2) The "DISPLAY" and "COMMENTS" columns in the /etc/shorewall/zones
   file have been removed and have been replaced by the former
   columns of the /etc/shorewall/ipsec file. The latter file has been
   removed.

   Additionally the FW option in shorewall.conf has been deprecated and
   is no longer set to 'fw' by default. New users are expected to
   define the firewall zone in /etc/shorewall/zones.

   Adhering to the principle of least astonishment, the old
   /etc/shorewall/ipsec file will continue to be supported. A new
   IPSECFILE variable in /etc/shorewall/shorewall.conf determines the
   name of the file that Shorewall looks in for IPSEC information. If
   that variable is not set or is set to the empty value then
   IPSECFILE=ipsec is assumed. So if you simply upgrade and don't do
   something idiotic like replace your current shorewall.conf file with
   the new one, your old configuration will continue to work. A dummy
   'ipsec' file is included in the release so that your package manager
   (e.g., rpm) won't remove your existing file.

   The shorewall.conf file included in this release sets
   IPSECFILE=zones so that new users are expected to use the new zone
   file format.

   As a result, the columns in the /etc/shorewall/zones file
   are now as follows:

	ZONE		Short name of the zone (5 Characters or less in
			length). The names "all" and "none" are
			reserved and may not be used as zone names.

			Where a zone is nested in one or more other
			zones, you may follow the (sub)zone name by ":"
			and a comma-separated list of the parent
			zones. The parent zones must have been defined
			in earlier records in this file.

			Example:

				#ZONE     TYPE     OPTIONS
				a	  ipv4
				b	  ipv4
				c:a,b     ipv4

		        Currently, Shorewall uses this information only
		        to reorder the zone list so that parent zones
		        appear after their sub zones in the list. In the
			future, Shorewall may make more extensive use
		        of that information.

	TYPE	ipv4 -	This is the standard Shorewall zone type and is
			the default if the column is left empty or if
			it is entered as "-".  Communication with some
			zone hosts may be encrypted. Encrypted hosts
			are designated using the 'ipsec' option in
			/etc/shorewall/hosts.
		ipsec -	Communication with all zone hosts is encrypted
			Your kernel and iptables must include policy
			match support.
		firewall
		      - Designates the firewall itself. You must have
			exactly one 'firewall' zone. No options are
			permitted with a 'firewall' zone.

	OPTIONS,		A comma-separated list of options as
	IN OPTIONS,		follows:
	OUT OPTIONS
				reqid=<number> where <number> is
				specified using setkey(8) using the
				'unique:<number> option for the SPD
				level.

				spi=<number> where <number> is the SPI
				of the SA used to encrypt/decrypt
				packets.

				proto=ah|esp|ipcomp

				mss=<number> (sets the MSS field in TCP
				packets)

				mode=transport|tunnel

				tunnel-src=<address>[/<mask>] (only
				available with mode=tunnel)

				tunnel-dst=<address>[/<mask>] (only
				available with mode=tunnel)


				strict  Means that packets must match
					all rules.


				next    Separates rules; can only be
					used with strict..

			Example:
				mode=transport,reqid=44

	The options in the OPTIONS column are applied to both
	incoming and outgoing traffic. The IN OPTIONS are
	applied to incoming traffic (in addition to OPTIONS)
	and the OUT OPTIONS are applied to outgoing traffic.

	If you wish to leave a column empty but need to make an
	entry in a following column, use "-".

   THE ORDER OF THE ENTRIES IN THIS FILE IS IMPORTANT IF YOU HAVE
   NESTED OR OVERLAPPING ZONES DEFINED THROUGH /etc/shorewall/hosts.


3) The DROPINVALID option has been removed from shorewall.conf. The
   behavior will be as if DROPINVALID=No had been specified. If you
   wish to drop invalid state packets, use the dropInvalid built-in
   action.

4) The 'nobogons' interface and hosts option as well as the
   BOGON_LOG_LEVEL option have been eliminated.

5) Most of the standard actions have been replaced by parametrized
   macros (see below). So for example, the action.AllowSMTP and
   action.DropSMTP have been removed an a parametrized macro
   macro.SMTP has been added to replace them.

   In order that current users don't have to immediately update their
   rules and user-defined actions, Shorewall can substitute an
   invocation of the a new macro for an existing invocation of one of
   the old actions. So if your rules file calls AllowSMTP, Shorewall
   will replace that call with SMTP/ACCEPT. Because this substitution
   is expensive, it is conditional based on the setting of
   MAPOLDACTIONS in shorewall.conf. If this option is set to YES or if
   it is not set (such as if you are using your old shorewall.conf
   file) then Shorewall will perform the substitution. Once you have
   converted to use the new macros, you can set MAPOLDACTIONS=No and
   invocations of those actions will go much quicker during 'shorewall
   [re]start'.

6) The STATEDIR variable in /etc/shorewall/shorewall.conf has been
   removed. STATEDIR is now fixed at /var/lib/shorewall. If you have
   previously set STATEDIR to another directory, please copy the files
   from that directory to /var/lib/shorewall/ before [re]starting
   Shorewall after the upgrade to this version.

7) The "shorewall status" command now just gives the status of
   Shorewall (started or not-started). The previous status command has
   been renamed "dump". The command also shows the state relative to the
   state diagram at
   http://shorewall.net/starting_and_stopping_shorewall.htm. In
   addition to the state, the time and date at which that state was
   entered is shown.

   Note that at least one "shorewall [re]start" must be issued after
   upgrading to this release before "shorewall status" will show
   anything but "Unknown" for the state.

8) The "shorewall forget" command now removes the dynamic blacklist
   save file (/var/lib/shorewall/save).

9) In previous versions of Shorewall, the rules generated by entries in
   /etc/shorewall/tunnels preceded those rules generated by entries in
   /etc/shorewall/rules. Beginning with this release, the rules
   generated by entries in the tunnels file will appear *AFTER* the
   rules generated by the rules file. This may cause you problems if
   you have REJECT, DENY or CONTINUE rules in your rules file that
   would cause the tunnel transport packets to not reach the rules that
   ACCEPT them. See http://www.shorewall.net/VPNBasics.html for
   information on the rules generated by entries in the tunnels file.

10) The NEWNOTSYN and LOGNEWNOTSYN options in shorewall.conf have been
    removed as have the 'newnotsyn' options in /etc/shorewall/interfaces
    and /etc/shorewall/hosts.

    TCP new-not-syn packets may be blocked using the 'dropNotSyn' or
    'rejNotSyn' built-in actions.

    Example: Reject all new-not-syn packets from the net and log them at
             the 'info' level.

	#ACTION          SOURCE           DEST           PROTO
	SECTION NEW
	rejNotSyn:info   net              all            tcp

    Note that the rule is added at the front of the NEW section of the
    rules file.

11) A new value is defined for the TC_ENABLED option in shorewall.conf to
    enable the built-in tc4shorewall traffic shaper. If you set
    TC_ENABLED=internal then tc4shorewall will be used.   If the option is
    set to Yes then Shorewall will continue to look for a 'tcstart' script.

New Features in Shorewall 3.0.*

1) Error and warning messages are made easier to spot by using
   capitalization (e.g., ERROR: and WARNING:).

2) A new option 'critical' has been added to
   /etc/shorewall/routestopped. This option can be used to enable
   communication with a host or set of hosts during the entire
   "shorewall [re]start/stop" process. Listing a host with this option
   differs from listing it without the option in several ways:

   a) The option only affect traffic between the listed host(s) and the
   firewall itself.

   b) If there are any entries with 'critical', the firewall
   will be completely opened briefly during start, restart and stop but
   there will be no chance of any packets to/from the listed host(s)
   being dropped or rejected.

   Possible uses for this option are:

   a) Root file system is NFS mounted. You will want to list the NFS server
   in the 'critical' option.

   b) You are running Shorewall in a Crossbeam environment
   (www.crossbeam.com). You will want to list the Crossbeam interface
   in this option

3) A new 'macro' feature has been added.

   Macros are very similar to actions and can be used in similar
   ways. The differences between actions and macros are as follows:

   a) An action creates a separate chain with the same name as the
      action (when logging is specified on the invocation of an action,
      a chain beginning with "%" followed by the name of the action and
      possibly followed by a number is created). When a macro is
      invoked, it is expanded in-line and no new chain is created.

   b) An action may be specified as the default action for a policy;
      macros cannot be specified this way.

   c) Actions must be listed in either /usr/share/shorewall/actions.std
      or in /etc/shorewall/actions. Macros are defined simply by
      placing their definition file in the CONFIG_PATH.

   d) Actions are defined in a file with a name beginning with
      "action." and followed by the name of the action. Macro files are
      defined in a file with a name beginning with "macro.".

   e) Actions may invoke other actions. Macros may not directly invoke
      other macros although they may invoke other macros indirectly
      through an action.

   f) DNAT[-] and REDIRECT[-] rules may not appear in an action. They
      are allowed in a macro with the restriction that the a macro
      containing one of these rules may not be invoked from an action.

   g) The values specified in the various columns when you invoke a
      macro are substituted in the corresponding column in each rule in
      the macro. The first three columns get special treatment:

      ACTION	 If you code PARAM as the action in a macro then
		 when you invoke the macro, you can include the
		 name of the macro followed by a slash ("/") and
		 an ACTION (either built-in or user-defined. All
		 instances of PARAM in the body of the macro will be
		 replaced with the ACTION.

		 Any logging applied when the macro is invoked is
		 applied following the same rules as for actions.

      SOURCE and
      DEST	 If the rule in the macro file specifies a value and
		 the invocation of the rule also specifies a value then
		 the value in the invocation is appended to the value
		 in the rule using ":" as a separator.

		 Example:

		 /etc/shorewall/macro.SMTP

		 PARAM		-	loc	tcp	25

		 /etc/shorewall/rules:

		 SMTP/DNAT:info		net	192.168.1.5

		 Would be equivalent to the following in the rules file:

		 DNAT:info	   net	loc:192.168.1.5	tcp	25

      Rest	 Any value in the invocation replaces the value in the
		 rule in the macro.

    One additional restriction applies to the mixing of macros and
    actions. Macros that are invoked from actions cannot themselves
    invoke other actions.

4)  If you have 'make' installed on your firewall, then when you use
    the '-f' option to 'shorewall start' (as happens when you reboot),
    if your /etc/shorewall/ directory contains files that were modified
    after Shorewall was last restarted then Shorewall is started using
    the config files rather than using the saved configuration.

5)  The 'arp_ignore' option has been added to /etc/shorewall/interfaces
    entries. This option sets
    /proc/sys/net/ipv4/conf/<interface>/arp_ignore. By default, the
    option sets the value to 1. You can also write arp_ignore=<value>
    where value is one of the following:

        1 - reply only if the target IP address is local address
        configured on the incoming interface

	2 - reply only if the target IP address	is local address
	configured on the incoming interface and both with the sender's
	IP address are part from same subnet on this interface

	3 - do not reply for local addresses configured with scope
	host, only resolutions for global and link addresses are
	replied

	4-7 - reserved

 	8 - do not reply for all local addresses

    WARNING -- DO NOT SPECIFY arp_ignore FOR ANY INTERFACE INVOLVED IN
    PROXY ARP.

6)  In /etc/shorewall/rules, "all+" in the SOURCE or DEST column works
    like "all" but also includes intrazone traffic. So the rule:

	 ACCEPT     loc		 all+	 tcp	   22

    would allow SSH traffic from loc->loc whereas

	 ACCEPT     loc		 all	 tcp	   22

    does not.

7)  A new FASTACCEPT option has been added to shorewall.conf.

    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 /etc/shorewall/rules.

8)  Shorewall now generates an error if the 'norfc1918' option is
    specified for an interface with an RFC 1918 address.

9)  You may now specify "!" followed by a list of addresses in the
    SOURCE and DEST columns of entries in /etc/shorewall/rules,
    /etc/shorewall/tcrules and in action files and Shorewall will
    generate the rule that you expect.

    Example 1 (/etc/shorewall/rules):

    #ACTION    SOURCE				DEST	PROTO     DEST PORT(S)
    ACCEPT     loc:!192.168.1.0/24,10.0.0.0/8	net	tcp	  80

    That rule would allow loc->net HTTP access except for the local
    networks 192.168.1.0/24 and 10.0.0.0/8.

    Example 2 (/etc/shorewall/rules):

    #ACTION    SOURCE				DEST	PROTO     DEST PORT(S)
    ACCEPT     loc:10.0.0.0/24!10.0.0.4,10.0.0.22 \
						net	tcp	  80

    That rule would allow loc->net HTTP access from the local
    network 10.0.0.0/24 except for hosts 10.0.0.4 and 10.0.0.22.

10) Tunnel types "openvpnserver" and "openvpnclient" have been added
    to reflect the introduction of client and server OpenVPN
    configurations in OpenVPN 2.0.

11) The COMMAND variable is now set to 'restore' in restore
    scripts. The value of this variable is sometimes of interest to
    programmers providing custom /etc/shorewall/tcstart scripts.

12) Previously, if you defined any intra-zone rule(s) then any traffic
    not matching the rule(s) was subject to normal policies (which
    usually turned out to involve the all->all REJECT policy). Now, the
    intra-zone ACCEPT policy will still be in effect in the presence of
    intra-zone rules. That policy can still be overridden by an
    explicit policy in your /etc/shorewall/policy file.

    Example:

    /etc/shorewall/rules:

    DNAT	loc:!192.168.1.4  loc:192.168.1.4:3128	tcp	80

    Any other loc->loc traffic will still be accepted. If you want to
    also log that other loc->loc traffic at the info log level then
    insert this into /etc/shorewall/policy:

    #SOURCE	DEST	POLICY	LOG LEVEL
    loc		loc	ACCEPT	info

13) Prior to Shorewall 2.5.3, the rules file only controlled packets in
    the Netfilter states NEW and INVALID. Beginning with this release,
    the rules file can also deal with packets in the ESTABLISHED and
    RELATED states.

    The /etc/shorewall/rules file may now be divided into
    "sections". Each section is introduced by a line that begins with
    the keyword SECTION followed by the section name. Sections
    are as listed below and must appear in the order shown.

    ESTABLISHED

	Rules in this section apply to packets in the ESTABLISHED
	state.

    RELATED

	Rules in this section apply to packets in the RELATED state.

    NEW

	Rules in this section apply to packets in the NEW and INVALID
	states.

    Rules in the ESTABLISHED and RELATED sections are limited to the
    following ACTIONs:

	ACCEPT, DROP, REJECT, QUEUE, LOG and User-defined actions.

    Macros may be used in these sections provided that they expand to
    only these ACTIONs.

    At the end of the ESTABLISHED and RELATED sections, there is an
    implicit "ALLOW   all	  all all" rule.

    RESTRICTION: If you specify FASTACCEPT=Yes in
    /etc/shorewall.shorewall.conf then the ESTABLISHED and RELATED
    sections must be empty.

14) The value 'ipp2p' is once again allowed in the PROTO column of
    the rules file. It is recommended that rules specifying 'ipp2p'
    only be included in the ESTABLISHED section of the file.


15) Shorewall actions lack a generalized way to pass parameters to an
    extension script associated with an action. To work around this
    lack, some users have used the log tag as a parameter. This works
    but requires that a log level other than 'none' be specified when
    the action is invoked. Beginning with this release, you can invoke
    an action with 'none'.

    Example:

	#ACTION				SOURCE          DEST
	A:none:these,are,parameters     $FW		net

    When /etc/shorewall/A is invoked, the LEVEL variable will be empty
    but the TAG variable will contain "these,are,parameters" which
    can be easily parsed to isolate "these", "are" and "parameters":

	ifs=$IFS
	IFS=,
	set -- $TAG
	IFS=$ifs

    Now, $1 = these, $2 = are and $3 = parameters

16) The "shorewall check" command now checks the /etc/shorewall/masq,
    /etc/shorewall/blacklist, /etc/shorewall/proxyarp,
    /etc/shorewall/nat and /etc/shorewall/providers files.

17) Arne Bernin's "tc4shorewall" package has been integrated into
    Shorewall.

    See: http://www.shorewall.net/3.0/traffic_shaping.htm for details.

    Thanks, Arne!

18) When /usr/share/shorewall/functions is loaded it now sets

	 SHOREWALL_LIBRARY=Loaded

    Application code such as /etc/shorewall/tcstart may test that
    variable to determine if the library has been loaded into the
    current shell process.

19) The install.sh script now does a much cleaner job of backing up the
    current installation. It copies the directories /etc/shorewall,
    /usr/share/shorewall and /var/lib/shorewall to a directory of the
    same name with "-$VERSION.bkout" appended. The init script and
    /sbin/shorewall are backed up to the /usr/share/shorewall and
    /var/lib/shorewall directories respectively. This makes it very
    simple to remove the backups:

	   rm -rf /etc/shorewall-*.bkout
	   rm -rf /usr/share/shorewall-*.bkout
	   rm -rf /var/lib/shorewall-*.bkout

20) A new '-n' option has been added to the "start", "restart",
    "restore",  "stop" and "try" commands. This option instructs
    Shorewall to not alter the routing in any way.

    This option is useful when you have a multi-ISP environment because
    it prevents the route cache from being flushed which preserves the
    mapping of end-point address pairs to routes.

21) The output of "shorewall dump" now includes a capabilities report
    such as the one produced by "shorewall show capabilities".

22) The "plain" zone type has been replaced by "ipv4". The types
    "IPv4" and "IPV4" are synonyms for "ipv4". In addition, "IPSEC",
    "ipsec4" and "IPSEC4" are recognized synonyms for "ipsec".

23) The NEWNOTSYN and LOGNEWNOTSYN options in shorewall.conf have been
    removed as have the 'newnotsyn' options in /etc/shorewall/interfaces
    and /etc/shorewall/hosts. See the Migration Considerations for
    instructions if you wish to block "new-not-syn" TCP packets.

24) The "shorewall show zones" command now displays the zone type. You
    must have restarted Shorewall using this release before this feature
    will work correctly.

25) The multi-ISP code now requires that that you set MARK_IN_FORWARD_CHAIN=Yes
    in shorewall.conf. This is done to ensure that "shorewall refresh" will
    work correctly.

26) Shorewall now supports UDP IPP2P matching. In addition to the "ipp2p"
    keyword in the PROTOCOL column of the relevant files, the following
    values may be specified:

	ipp2p:tcp           Equivalent to ipp2p and matches TCP traffic
			    only.
	ipp2p:udp           Matches UDP traffic.
	ipp2p:all           Matches both UDP and TCP traffic. You may
			    not specify a SOURCE PORT with this PROTOCOL.

27) Normally MAC verification triggered by the 'maclist' interface and host
    options is done out of the INPUT and FORWARD chains of the filter table.
    Users have reported that under some circumstances, MAC verification is
    failing for forwarded packets when the packets are being forwarded out
    of a bridge.

    To work around this problem, a MACLIST_TABLE option has been added to
    shorewall.conf. The default value is MACLIST_TABLE=filter which results
    in the current behavior. If MACLIST_TABLE=mangle then filtering will
    take place out of the PREROUTING chain of the mangle table. Because
    the REJECT target may not be used in the PREROUTING chain, the settings
    MACLIST_DISPOSITION=REJECT and MACLIST_TABLE=mangle are incompatible.

28) The sample configurations are now packaged with the product. They are
    in the Samples directory on the tarball and are in the RPM they are
    in the Samples sub-directory of the Shorewall documentation
    directory.