depending on your definition of 'trivial', passive FTP is trivially tested:

grunion:~ emileaben$ telnet ftp.freebsd.org 21
Trying 204.152.184.73...
Connected to ftp.freebsd.org.
Escape character is '^]'.
220 Welcome to freebsd.isc.org.
USER anonymous
331 Please specify the password.
PASS [EMAIL PROTECTED]
230-
230-You have reached the freebsd.isc.org FTP server, serving the
230-full FreeBSD FTP archive over IPv4 (204.152.184.73) and IPv6
230-(2001:4f8:0:2::e) networks.  This server is also known as:
230-
230-    ftp.freebsd.org
230-    ftp4.freebsd.org
230-    ftp4.us.freebsd.org
230-
230-This server is operated by Internet Systems Consortium (ISC),
230-on behalf of the FreeBSD Project, with hardware donations from
230-Apple, Intel and Iron Systems.
230-
230-Questions about this service can be sent to: [EMAIL PROTECTED]
230-
230 Login successful.
PASV
227 Entering Passive Mode (204,152,184,73,127,51)
LIST

(here comes the somewhat less trivial part):
Open a new shell somewhere, and calculate where the 'ls' output is going
from the 227-passive FTP line, first 4 octets are the IP address,
in this case it's 204.152.184.73, last 2 octets are the portnumber:
127 * 256 + 51 = 32563

So I can retrieve the 'ls' output by:

grunion:~ emileaben$ telnet 204.152.184.73 32563
Trying 204.152.184.73...
Connected to freebsd.isc.org.
Escape character is '^]'.
drwxrwxr-x    3 0        0             512 Apr 17  2003 pub
Connection closed by foreign host.
grunion:~ emileaben$

unfortunately this doesn't work for active FTP (since the server will
initiate a connection to you), you could use 'netcat' or something to
catch that.

hth,
emile

On 3/27/06, Stewart Stremler <[EMAIL PROTECTED]> wrote:
> begin  quoting Tracy R Reed as of Mon, Mar 27, 2006 at 10:23:16AM -0800:
> > Stewart Stremler wrote:
> > > FTP is a protocol that's not easily testable with a telnet client.
> >
> > Neither is ntp, nfs, rdp, X, or a zillion others. Being easily testable
> > with telnet just means the protocol is trivial.
>
> Um, no.
>
> "Easily testable with telne" != "trivial".
>
> But that's beside the point.
>
> FTP *could* have been... the other big file-transfer protocol out there
> these days _is_ testable with telnet.
>
> > > You like default-allow security policies then?
> >
> > No, I like default-deny. That has nothing to do with NAT though.
>
> NAT enforces a default-deny policy.  It has some other limitations,
> which is where most anti-NAT folks scream and shout... but if you
> hit those limitations, you really need to move up to proxy firewalls.
>
> Which, oddly enough, look like NAT to the outside world... all users
> behind it generally share one IP.
>
> --
> _ |\_
>  \|
>
>
> --
> [email protected]
> http://www.kernel-panic.org/cgi-bin/mailman/listinfo/kplug-list
>


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