@(#) BLURB 1.28 97/03/21 19:27:18
With this package you can monitor and filter incoming requests for the
SYSTAT, FINGER, FTP, TELNET, RLOGIN, RSH, EXEC, TFTP, TALK, and other
The package provides tiny daemon wrapper programs that can be installed
without any changes to existing software or to existing configuration
files. The wrappers report the name of the client host and of the
requested service; the wrappers do not exchange information with the
client or server applications, and impose no overhead on the actual
conversation between the client and server applications.
This patch upgrades the tcp wrappers version 7.5 source code to
version 7.6. The source-routing protection in version 7.5 was not
as strong as it could be. And all this effort was not needed with
modern UNIX systems that can already stop source-routed traffic in
the kernel. Examples are 4.4BSD derivatives, Solaris 2.x, and Linux.
This release does not introduce new features. Do not bother applying
this patch when you built your version 7.x tcp wrapper without
enabling the KILL_IP_OPTIONS compiler switch; when you can disable
IP source routing options in the kernel; when you run a UNIX version
that pre-dates 4.4BSD, such as SunOS 4. Such systems are unable to
receive source-routed connections and are therefore not vulnerable
to IP spoofing attacks with source-routed TCP connections.
A complete change log is given in the CHANGES document. As always,
problem reports and suggestions for improvement are welcome.
Wietse Venema (firstname.lastname@example.org),
Department of Mathematics and Computing Science,
Eindhoven University of Technology,
Currently visiting IBM T.J. Watson Research, Hawthorne NY, USA.