This is netkit-telnet-0.18-pre1 for Linux.

This is a PRERELEASE version. It should only be used by people willing
to deal with the possible consequences of using half-baked software.

If you received this version with a Linux distribution, please switch
to an official release immediately and complain to the maintainers of
your distribution.

This package updates netkit-telnet-0.17.

If you're reading this off a CD, go right away and check the net
archives for later versions and security fixes. As of this writing the
home site for NetKit is
	ftp://ftp.uk.linux.org/pub/linux/Networking/netkit

Contents:
	telnet		Client for telnet protocol
	telnetd		Daemon for telnet protocol

Note: These programs do not provide encryption or strong
authentication of network connections. As such, their use for remote
logins is discouraged. The "ssh" protocol, in one of its several
implementations, can be used instead.

Requires:
	Working compiler, libc, and kernel, and a recent version of
	ncurses or libtermcap.

	Note that while telnet uses the C++ compiler, it neither requires
	nor uses libstdc++.

Security:
	This release contains fixes for systemic buffer handling
	problems in telnetd that were probably vulnerable to a wide
	range of attacks. Please update. netkit-telnet-0.17 and
	earlier should not be used.

	Even after these fixes, telnetd is still evil legacy code and
	is not trustworthy. Do not run it unless you absolutely need it.

	This release contains experimental login wrapper code to permit
	running telnetd as a non-root user. This code is not built by 
	default. Look in the "telnetlogin" directory and the telnetlogin 
	man page contained therein for more information.

Old kernels:
	If you have an old kernel, you may need to apply the enclosed
	pty-hang patch to it. I don't unfortunately know at the moment 
	which kernel versions need the patch, but current 2.0.x and
	2.2.x should be ok without it.

	The following test will tell you if you need the patch: telnet
	to localhost, do "cat >/dev/null", and type 256 characters
	without any newlines. If you need the patch, telnetd will hang
	completely at this point. If it refuses to accept more input,
	but does not hang, you do not need the patch.

Installation:
	Do "./configure --help" and decide what options you want. The
	defaults should be suitable for most Linux systems. Then run
	the configure script.

	Do "make" to compile.
	Then (as root) do "make install".

	Save a backup copy of any mission-critical program in case the
	new one doesn't work, and so forth. We warned you.

	If you get gcc warnings from files in /usr/include, they are
	due to problems in your libc, not netkit. (You may only see
	them when compiling netkit because netkit turns on a lot of
	compiler warnings.)

DEC CC:
	DEC released their Alpha compiler for use on Linux as freeware.
	It is a much better compiler with gcc, that is, it generates
	much better code. If you have the DEC compiler, you can
	explicitly use the DEC compiler instead of gcc by configuring
	like this:

		./configure --with-c-compiler=ccc

	Please report any problems you encounter using it.


	Note that there is no corresponding C++ compiler, so telnet
	will be compiled with g++ anyway.

Bugs:
	Please make sure the header files in /usr/include match the
	libc version installed in /lib and /usr/lib. This is a fairly
	common source of weird problems.

	Also, before reporting a bug, be sure you're working with the
	latest version.

	If something doesn't compile for you, fix it and send diffs.
	If you can't, send the compiler's error output.

	If it compiles but doesn't work, send as complete a bug report as 
	you can. Patches and fixes are welcome, as long as you describe 
	adequately what they're supposed to fix. Please, one patch per
	distinct fix. Please do NOT send the whole archive back or
	reindent the source.

	Be sure to send all correspondence in e-mail to the netkit address.
	Postings to netnews or mailing lists will not be seen due to the 
	enormous volume. Also, anything that doesn't get filed in the bug
	database is quite likely to end up forgotten.

	Please don't report known bugs (see the BUGS file(s)) unless you
	are including fixes. :-)

	Mail should be sent to: netbug@ftp.uk.linux.org

	Note that (due to the spam problem) this address does not have
	an autoresponder, so mail may not be answered rapidly. However,
	it does eventually get read.



NetKit 0.18 has been pushed out the door before it was really properly
ready. It does not include everything that it might - many patches
that have been received have not been merged yet. I do not have a
whole lot of time to spare for netkit, so while I hope to get another
release out with some of those patches before too long, it may take
quite a while.

The netkit web page may be found at http://www.linux.org.uk/~netbug.

David A. Holland
1 August 2002
