IMPORTANT
If you use a Windows system to download a corrected script, be sure to run the script through dos2unix after you have moved it to your Linux system.
If you are installing Shorewall for the first time and plan to use the .tgz and install.sh script, you can untar the archive, replace the 'firewall' script in the untarred directory with the one you downloaded below, and then run install.sh.
When the instructions say to install a corrected firewall script in /etc/shorewall/firewall or /var/lib/shorewall/firewall, use the 'cp' (or 'scp') utility to overwrite the existing file. DO NOT REMOVE OR RENAME THE OLD /etc/shorewall/firewall or /var/lib/shorewall/firewall before you do that. /etc/shorewall/firewall and /var/lib/shorewall/firewall are symbolic links that point to the 'shorewall' file used by your system initialization scripts to start Shorewall during boot. It is that file that must be overwritten with the corrected script.
If you have a pair of firewall systems configured for failover, you will need to modify your firewall setup slightly under Shorewall versions >= 1.3.6.
Create the file /etc/shorewall/newnotsyn and in it add
the following rule
run_iptables -A newnotsyn -j RETURN # So that the
connection tracking table can be rebuilt
# from non-SYN packets after takeover.
Create /etc/shorewall/common (if you don't already
have that file) and include the following:
run_iptables -A common -p tcp --tcp-flags
ACK,FIN,RST ACK -j ACCEPT #Accept Acks to rebuild connection
#tracking table.
. /etc/shorewall/common.def
Some forms of pre-1.3.0 rules file syntax are no longer supported.
Example 1:
ACCEPT net loc:192.168.1.12:22 tcp 11111 - all
Must be replaced with:
DNAT net loc:192.168.1.12:22 tcp 11111
Example 2:
ACCEPT loc fw::3128 tcp 80 - all
Must be replaced with:
REDIRECT loc 3128 tcp 80
The new 'proxyarp' interface option doesn't work :-( This is fixed in this corrected firewall script which must be installed in /var/lib/shorewall/ as described above.
Prior to version 1.3.4, host file entries such as the following were allowed:
adm eth0:1.2.4.5,eth0:5.6.7.8
That capability was lost in version 1.3.4 so that it is only possible to include a single host specification on each line. This problem is corrected by this modified 1.3.5a firewall script. Install the script in /var/lib/pub/shorewall/firewall as instructed above.
This problem is corrected in version 1.3.5b.
REDIRECT rules are broken in this version. Install this corrected firewall script in /var/lib/pub/shorewall/firewall as instructed above. This problem is corrected in version 1.3.5a.
The "shorewall start" and "shorewall restart" commands to not verify that the zones named in the /etc/shorewall/policy file have been previously defined in the /etc/shorewall/zones file. The "shorewall check" command does perform this verification so it's a good idea to run that command after you have made configuration changes.
If you have upgraded from Shorewall 1.2 and after "Activating rules..." you see the message: "iptables: No chains/target/match by that name" then you probably have an entry in /etc/shorewall/hosts that specifies an interface that you didn't include in /etc/shorewall/interfaces. To correct this problem, you must add an entry to /etc/shorewall/interfaces. Shorewall 1.3.3 and later versions produce a clearer error message in this case.
Until approximately 2130 GMT on 17 June 2002, the download sites contained an incorrect version of the .lrp file. That file can be identified by its size (56284 bytes). The correct version has a size of 38126 bytes.
Both problems are corrected in this script which should be installed in /var/lib/shorewall as described above.
The IANA have just announced the allocation of subnet 221.0.0.0/8. This updated rfc1918 file reflects that allocation.
These problems are corrected in this firewall script which should be installed in /etc/shorewall/firewall as described above.
There are a couple of serious bugs in iptables 1.2.3 that prevent it from working with Shorewall. Regrettably, RedHat released this buggy iptables in RedHat 7.2.
I have built a corrected 1.2.3 rpm which you can download here and I have also built an iptables-1.2.4 rpm which you can download here. If you are currently running RedHat 7.1, you can install either of these RPMs before you upgrade to RedHat 7.2.
Update 11/9/2001: RedHat has released an iptables-1.2.4 RPM of their own which you can download from http://www.redhat.com/support/errata/RHSA-2001-144.html. I have installed this RPM on my firewall and it works fine.
If you would like to patch iptables 1.2.3 yourself, the patches are available for download. This patch which corrects a problem with parsing of the --log-level specification while this patch corrects a problem in handling the TOS target.
To install one of the above patches:
- cd iptables-1.2.3/extensions
- patch -p0 < the-patch-file
Users who use RedHat iptables RPMs and who upgrade to kernel 2.4.18/19 may experience the following:
# shorewall start Processing /etc/shorewall/shorewall.conf ... Processing /etc/shorewall/params ... Starting Shorewall... Loading Modules... Initializing... Determining Zones... Zones: net Validating interfaces file... Validating hosts file... Determining Hosts in Zones... Net Zone: eth0:0.0.0.0/0 iptables: libiptc/libip4tc.c:380: do_check: Assertion `h->info.valid_hooks == (1 << 0 | 1 << 3)' failed. Aborted (core dumped) iptables: libiptc/libip4tc.c:380: do_check: Assertion `h->info.valid_hooks == (1 << 0 | 1 << 3)' failed. Aborted (core dumped)The RedHat iptables RPM is compiled with debugging enabled but the user-space debugging code was not updated to reflect recent changes in the Netfilter 'mangle' table. You can correct the problem by installing this iptables RPM. If you are already running a 1.2.5 version of iptables, you will need to specify the --oldpackage option to rpm (e.g., "iptables -Uvh --oldpackage iptables-1.2.5-1.i386.rpm").
If you find that rpm complains about a conflict with kernel <= 2.2 yet you have a 2.4 kernel installed, simply use the "--nodeps" option to rpm.
Installing: rpm -ivh <shorewall rpm>
Upgrading: rpm -Uvh <shorewall rpm>
Problems with iptables version 1.2.7 and MULTIPORT=Yes
The iptables 1.2.7 release of iptables has made an incompatible change to the syntax used to specify multiport match rules; as a consequence, users who install iptables 1.2.7 must set MULTIPORT=No in /etc/shorewall/shorewall.conf or install this firewall script in /var/lib/shorewall/firewall as described above.
Last updated 8/14/2002 - Tom Eastep