Quoting Rafael 'Dido' Sevilla ([EMAIL PROTECTED]):
> On Fri, Mar 22, 2002 at 03:17:35PM +0800, Eliel Antero S. Roxas wrote:
>> Hello Evryone!
>> 
>> I am trying to set up an FTP server in Red Hat 7.1.
> 
> Forget about installing it.  I'm serious.
> 
> I would strongly suggest that you ditch the FTP server completely, or
> leave it at anonymous-only download if that's what you want.

The latter is what I do -- currently using vs-ftpd.  I keep a list of 
known ftpds, with comments on security and other matters, at
http://linuxmafia.com/pub/linux/security/ftp-daemons .  Many problems
people attribute to ftpds are just a matter of people not thinking to
use something better than wu-ftpd.  

But there are also other pitfalls often considered inherent to
non-anonymous ftp.  Let's consider them:

> Non-anonymous FTP is very dangerous in today's world, as it performs
> authentication without cryptography, which is a complete joke.  

This isn't necessarily a problem.  It's a problem if (1) ftp users have 
wide access to the filesystem, and (2) ftp exposes passwords also usable
for shell access.  But nobody says either of those things _needs_ to be
true.

o   Chroot non-anonymous users to subdirectories of their home
    directories.  ~/public_html might be good enough.
o   And you _do_ already apply quota to the /home tree, right?
o   Compile your ftpd to authenticate against a separate password
    file, not the main system authentication database.

An ftpd compiled and operated that way will not create the hazard you
describe.

Mind you, some years ago, I shut off non-anonymous ftpd (and POP3[1]) on
my systems for exactly the reason you described.   It's only recently
that I realised there _are_ ways to offer the service that don't suffer
the obvious threat model.

> As I have said over and over, FTP is a relic of a time when the
> Internet was a research network where everyone could trust everyone
> else.

Please note that it has some unique advantages:
http://linuxmafia.com/~rick/linux-info/ftp-justification

[1] APOP isn't widely enough supported to be a reasonable option, and
requires having a plaintext password file sitting around.  SSL-wrapped
POP3 works fine, but you have to really twist your users' arms to get
them to set up the client side.

-- 
Cheers,
Rick Moen                     Emacs is a decent operating system,
[EMAIL PROTECTED]           but it still lacks a good text editor.
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