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I am trying to configure the telnetd service daemon on Gentoo.

I first installed the internet superserver daemon:

emerge netkit-base

I next installed the telnetd server daemon:

emerge netkit-telnetd

I next created a user and group for the telnetd server daemon:

groupadd -g 300 telnetd
useradd -u 300 -g 300 telnetd

I now modified the telnetd account in /etc/passwd as follows:

telnetd:x:300:300::/nonexistent:/bin/false

(This line is copied from a working telnet server)

Then I created the /etc/inetd.conf configuration file for the internet
superservice daemon with the following entry:

telnet stream tcp nowait telnetd /usr/sbin/telnetd

Next I start the internet superserver daemon as follows:

/etc/init.d/inetd start
* Starting inetd ...

Now I telnet the localhost:

telnet localhost
Trying 127.0.0.1 ...
Connected to localhost.localdomain.
Escape character is ']'

Linux 2.6.23.9 (despina.markhobley.yi.org) (1)
login: Permission Denied.
Connection closed by foreign host.


The error at the login prompt appears before I type in the username, so
I think the error is related somehow to the login program.

I presume that the login: prompt is being generated by the login
program, and then the program is exiting before user input can be
collected, so I suspect the login program was running, but I don't know
for sure. I guess that somehow I have to make a configuration
change to allow the login program to be used from the telnet virtual
terminal. (Then again, I might be wrong.)

Thanks in advance to anyone who can help with this.

Mark.

--
Mark Hobley,
393 Quinton Road West,
Quinton, BIRMINGHAM.
B32 1QE.

Mark Hobley wrote:
> I am trying to configure the telnetd service daemon on Gentoo.
>
> I first installed the internet superserver daemon:
>
> emerge netkit-base
>
> I next installed the telnetd server daemon:
>
> emerge netkit-telnetd
>
> I next created a user and group for the telnetd server daemon:
>
> groupadd -g 300 telnetd
> useradd -u 300 -g 300 telnetd
>
> I now modified the telnetd account in /etc/passwd as follows:
>
> telnetd:x:300:300::/nonexistent:/bin/false
>
> (This line is copied from a working telnet server)
>
> Then I created the /etc/inetd.conf configuration file for the internet
> superservice daemon with the following entry:
>
> telnet stream tcp nowait telnetd /usr/sbin/telnetd

Mine says

telnet stream tcp nowait telnetd.telnetd /usr/sbin/tcpd
/usr/sbin/in.telnetd


>
> Next I start the internet superserver daemon as follows:
>
> /etc/init.d/inetd start
> * Starting inetd ...
>
> Now I telnet the localhost:
>
> telnet localhost
> Trying 127.0.0.1 ...
> Connected to localhost.localdomain.
> Escape character is ']'
>

Thats the telnetd working then..at some level

> Linux 2.6.23.9 (despina.markhobley.yi.org) (1)
> login: Permission Denied.
> Connection closed by foreign host.
>

Thats login crapping out. Permissions of some sort.

..

>
> The error at the login prompt appears before I type in the username, so
> I think the error is related somehow to the login program.
>

So do I.

> I presume that the login: prompt is being generated by the login
> program, and then the program is exiting before user input can be
> collected, so I suspect the login program was running, but I don't know
> for sure. I guess that somehow I have to make a configuration
> change to allow the login program to be used from the telnet virtual
> terminal. (Then again, I might be wrong.)
>

Never had a problem.


If you can get a root prompt do an:

su - telnetd

And then try :

/bin/login

Thats is close to the permissions it will be running at

Likewise, look in the log files.



> Thanks in advance to anyone who can help with this.
>
> Mark.
>

Mark Hobley wrote:

> Then I created the /etc/inetd.conf configuration file for the internet
> superservice daemon with the following entry:
>
> telnet stream tcp nowait telnetd /usr/sbin/telnetd
>
> Next I start the internet superserver daemon as follows:

Why not use the xinted instead?
or why not use ssh?


> Now I telnet the localhost:
>
> telnet localhost
> Trying 127.0.0.1 ...
> Connected to localhost.localdomain.
> Escape character is ']'
> Linux 2.6.23.9 (despina.markhobley.yi.org) (1)
> login: Permission Denied.
> Connection closed by foreign host.
> The error at the login prompt appears before I type in the username, so
> I think the error is related somehow to the login program.

What do you get in the messages log file?


--

//Aho

In alt.os.linux.gentoo J.O. Aho <user@example.net> wrote:

> Why not use the xinted instead?

I prefer inetd, it is less resource intesive, and I am using it on all
of my other stations. I try and use the same software across all
stations, where possible.

> or why not use ssh?

The ssh tool encrypts the network traffic making it difficult to
analyse. I don't want encrypted traffic on the local area network.

> What do you get in the messages log file?

This is a new installation, and the system logging mechanisms are not
yet operational. I was hoping to fix this after fixing the remote
access via telnet. I am new to Gentoo, so I am still learning how to
configure it. I am currently working on getting the system loggine
mechanisms operational.

Mark.

--
Mark Hobley,
393 Quinton Road West,
Quinton, BIRMINGHAM.
B32 1QE.

["Followup-To:" header set to comp.os.linux.misc.]
Mark Hobley staggered into the Black Sun and said:
> In alt.os.linux.gentoo J.O. Aho <user@example.net> wrote:
>> Why not use the xinted instead?
> I prefer inetd, it is less resource intesive, and I am using it on all
> of my other stations. I try and use the same software across all
> stations, where possible.
>> or why not use ssh?
> The ssh tool encrypts the network traffic making it difficult to
> analyse. I don't want encrypted traffic on the local area network.

Um... why would you need to analyze this traffic? Also, ssh, when set
up properly, is more *convenient* than telnet. Don't forget ssh's X11
forwarding capabilities, necessary since most modern X installs are
started with '-nolisten tcp'.

>> What do you get in the messages log file?
> This is a new installation, and the system logging mechanisms are not
> yet operational. I was hoping to fix this after fixing the remote
> access via telnet. I am new to Gentoo, so I am still learning how to
> configure it. I am currently working on getting the system loggine
> mechanisms operational.

Like section 9.a of the Gentoo Handbook says,
emerge syslog-ng
rc-update add syslog-ng default
/etc/init.d/syslog-ng start

....you should've done that or something similar during initial install.
The default syslog-ng config, located in /etc/conf.d/ , should get
you something sensible. Most of the config files for the init scripts
are in /etc/conf.d/ .

--
Sometimes I lie awake at night, and I ask, "Where have I gone wrong?"
Then a voice says to me, "This is going to take more than one night."
Charles M. Schulz (1922 - 2000), Charlie Brown in "Peanuts"
Matt G|There is no Darkness in Eternity/But only Light too dim for us to see

markhobley@hotpop.donottypethisbit.com (Mark Hobley) writes:


> I am trying to configure the telnetd service daemon on Gentoo.
>
> I first installed the internet superserver daemon:
>
> emerge netkit-base

There's another telnetd in Gnu's inetutils. That's the one I have
here, if you can't make a go with this one. Plus, I'm not sure the
net-kit one is even being maintained anymore, which might be a security
concern. For that matter, I think inetutils includes an inetd as well.

> I now modified the telnetd account in /etc/passwd as follows:
>
> telnetd:x:300:300::/nonexistent:/bin/false

Some apps crap out with a bogus home directory. That may or may not be
the case here, but I thought I'd mention it.


> telnet localhost
> Trying 127.0.0.1 ...
> Connected to localhost.localdomain.
> Escape character is ']'

inetd's done its part ... looks like telnetd's passed control to login
when it hits trouble.

> Linux 2.6.23.9 (despina.markhobley.yi.org) (1)
> login: Permission Denied.
> Connection closed by foreign host.

Are you sure your telnetd can run as an unpriv. user?


> The error at the login prompt appears before I type in the username, so
> I think the error is related somehow to the login program.
>
> I presume that the login: prompt is being generated by the login
> program, and then the program is exiting before user input can be
> collected, so I suspect the login program was running, but I don't know
> for sure. I guess that somehow I have to make a configuration
> change to allow the login program to be used from the telnet virtual
> terminal. (Then again, I might be wrong.)


I'd test with setting a real path for the home dir., and running as
root. See if it clears up, and decide from there what to do. Also, if
the daemon needs some command line options, make sure those are OK
too, check out the man page. Maybe try to run it stand-alone without
inetd, and get it working like that before putting it under inetd.


--
[** America, the police state **]
Whoooose! What's that noise? Why, it's US citizen's
rights, going down the toilet with Bush flushing.
http://www.wired.com/politics/securi...007/08/wiretap
http://www.hermes-press.com/police_state.htm
http://www.privacyinternational.org/...D=x-347-559597

In alt.os.linux.gentoo jayjwa <jayjwa@vdrl.ath.cx.invalid> wrote:

> inetd's done its part ... looks like telnetd's passed control to login
> when it hits trouble.

Ok.

> Are you sure your telnetd can run as an unpriv. user?

I don't know. I just tried this as root in inetd.conf and the telnet
daemon works fine, and I can login.

Looking at my (working) Debian computers, the telnetd daemon is run as
an unprivileged user. I thought I was using the same telnetd package.
The man pages certainly match, beginning:

TELNETD(8) BSD System Manager's Manual TELNETD(8)

NAME
telnetd -- DARPA telnet protocol server

> I'd test with setting a real path for the home dir., and running as
> root. See if it clears up, and decide from there what to do.

Running as root works. It is weird that I don't have to do that in
Debian.

Mark.

--
Mark Hobley,
393 Quinton Road West,
Quinton, BIRMINGHAM.
B32 1QE.

Mark Hobley wrote:
> In alt.os.linux.gentoo jayjwa <jayjwa@vdrl.ath.cx.invalid> wrote:
>
>> inetd's done its part ... looks like telnetd's passed control to login
>> when it hits trouble.
>
> Ok.
>
>> Are you sure your telnetd can run as an unpriv. user?
>
> I don't know. I just tried this as root in inetd.conf and the telnet
> daemon works fine, and I can login.
>
> Looking at my (working) Debian computers, the telnetd daemon is run as
> an unprivileged user. I thought I was using the same telnetd package.
> The man pages certainly match, beginning:
>
> TELNETD(8) BSD System Manager's Manual TELNETD(8)
>
> NAME
> telnetd -- DARPA telnet protocol server
>
>> I'd test with setting a real path for the home dir., and running as
>> root. See if it clears up, and decide from there what to do.
>
> Running as root works. It is weird that I don't have to do that in
> Debian.
>
> Mark.
>
Puzzles me too.


Nether telnetd nor login are suid root on my system..though inetd is
running as root.

And my login process is also root. Odd that since its spawned by
telnetd, which isn't..

Debian sarge..

Ahh. A probe into the guts of the telnetd program reveals
"/usr/lib/telnetlogin:" which IS SUID root, and is called by telnetd.

ls -l /usr/lib/telnetlogin
-rwsr-xr-- 1 root telnetd 6032 2005-10-09 17:24 /usr/lib/telnetlogin


So that's something to check on the OP's system, if thats not SUID root,
it wont be able to work properly.

In alt.os.linux.gentoo The Natural Philosopher <a@b.c> wrote:

> Ahh. A probe into the guts of the telnetd program reveals
> "/usr/lib/telnetlogin:" which IS SUID root, and is called by telnetd.
>
> ls -l /usr/lib/telnetlogin
> -rwsr-xr-- 1 root telnetd 6032 2005-10-09 17:24 /usr/lib/telnetlogin

Ok, that is interesting. I have that file on the working Debian system,
but on Gentoo the file is located in /usr/sbin/telnetlogin

> So that's something to check on the OP's system, if thats not SUID root,
> it wont be able to work properly.

Ok, that file was not suid, and did not belong to the telnetd group. I
have fixed this.

However, I still get the permission denied error, if I run the telnetd
as user telnetd in inetd.conf

On the Debian system user telnetd is a member of utmp. I have added
telnetd to the utmp group on Gentoo. (I don't know why this is
configured as so.)

Mark.

--
Mark Hobley,
393 Quinton Road West,
Quinton, BIRMINGHAM.
B32 1QE.