Shorewall Errata
Tom
Eastep
2004-03-20
2001-2004
Thomas M. Eastep
Permission is granted to copy, distribute and/or modify this
document under the terms of the GNU Free Documentation License, Version
1.2 or any later version published by the Free Software Foundation; with
no Invariant Sections, with no Front-Cover, and with no Back-Cover
Texts. A copy of the license is included in the section entitled
GNU Free Documentation License
.
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 /usr/share/shorewall/firewall, you may rename the existing file
before copying in the new file.
DO NOT INSTALL CORRECTED COMPONENTS ON A
RELEASE EARLIER THAN THE ONE THAT THEY ARE LISTED UNDER BELOW.
For example, do NOT install the 1.3.9a firewall script if you are
running 1.3.7c.
RFC1918 File
Here
is the most up to date version of the rfc1918 file. This file only
applies to Shorewall version 2.0.0 and its bugfix updates. In Shorewall
2.0.1 and later releases, the bogons file lists IP
ranges that are reserved by the IANA and the rfc1918
file only lists those three ranges that are reserved by RFC 1918.
Problems in Version 2.0
Shorewall 2.0.0
When using an Action in the ACTIONS column of a rule, you may
receive a warning message about the rule being a policy. While this
warning may be safely ignored, it can be eliminated by installing
the script from the link below.
Thanks to Sean Mathews, a long-standing problem with Proxy ARP
and IPSEC has been corrected.
The first problem has been corrected in Shorewall update 2.0.0a.
All of these problems may be corrected by installing this
firewall script in /usr/share/shorewall as described above.
Upgrade Issues
The upgrade issues have moved to a
separate page.
Problem with iptables version 1.2.3
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
Problems with kernels >= 2.4.18 and RedHat iptables
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
).
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, if you install iptables 1.2.7 you must be running Shorewall
1.3.7a or later or:
set MULTIPORT=No in /etc/shorewall/shorewall.conf; or
If you are running Shorewall 1.3.6 you may install this
firewall script in /usr/lib/shorewall/firewall as described
above.
Problems with RH Kernel 2.4.18-10 and NAT
/etc/shorewall/nat entries of the following form will result in
Shorewall being unable to start:
#EXTERNAL INTERFACE INTERNAL ALL INTERFACES LOCAL
192.0.2.22 eth0 192.168.9.22 yes yes
#LAST LINE -- ADD YOUR ENTRIES ABOVE THIS LINE -- DO NOT REMOVE
Error message is:
Setting up NAT...
iptables: Invalid argument
Terminated
The solution is to put no
in the LOCAL column. Kernel
support for LOCAL=yes has never worked properly and 2.4.18-10 has disabled
it. The 2.4.19 kernel contains corrected support under a new kernel
configuraiton option; see http://www.shorewall.net/Documentation.htm#NAT.
Problems with RH Kernels after 2.4.20-9 and REJECT (also applies to
2.4.21-RC1)
Beginning with errata kernel 2.4.20-13.9, REJECT
--reject-with tcp-reset
is broken. The symptom most commonly seen
is that REJECT rules act just like DROP rules when dealing with TCP. A
kernel patch and precompiled modules to fix this problem are available at
ftp://ftp1.shorewall.net/pub/shorewall/errata/kernel
RedHat have corrected this problem in their 2.4.20-27.x kernels.
Revision History4
1.62004-03-20TEProxy
ARP/IPSEC fix.1.62004-03-17TEAction
rules are reported as policies.1.52004-02-03TEUpdate
for Shorewall 2.0.0.1.42004-01-19TEIPV6
address problems. Make RFC1918 file section more prominent.1.32004-01-14TEConfusing
template file in 1.4.91.32004-01-03TEAdded
note about REJECT RedHat Kernal problem being corrected.1.22003-12-29TEUpdated
RFC1918 file1.12003-12-17TEInitial
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