Run script when someone telnet my server

Question

I Have:

1) Droplets on DigitalOcean ubuntu/debian/fedora

2) Simple script that echoes something "script.sh"

I want:

When someone telnets my Server from terminal: telnet MY_DROPLET_IP make my script.sh execute in his terminal and exit after that.

To sum up, I need something like this(check this out): telnet towel.blinkenlights.nl

score 1 · Answer 1 · edited May 23 '17 at 11:58

1

As telnet does not require a handshake, you could set up xinetd to run the script on connections to port 23.

edited May 23 '17 at 11:58

Community

1
1

answered Feb 19 '15 at 23:49

that other guy

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Thanks, helped a lot. I've solved issue and explained in my answer. – natchkebiailia Feb 20 '15 at 00:40

natchkebiailia · Accepted Answer · 2016-07-15T13:09:15.427

installation:

sudo apt-get install xinetd telnetd

/etc/xinetd.d/telnet file content:

service login
{
    port            = 23 
    socket_type     = stream
    protocol        = tcp
    wait            = no
    user            = root
    server          = /usr/bin/script.sh       
    server_args     = test
}

/etc/xinetd.conf content:

{
# Please note that you need a log_type line to be able to use log_on_success
# and log_on_failure. The default is the following :
# log_type = SYSLOG daemon info
instances = 60
log_type = SYSLOG authpriv
log_on_success = HOST PID
log_on_failure = HOST
cps = 25 30
}

includedir /etc/xinetd.d

/etc/inetd.conf content:

telnet      stream  tcp nowait telnetd  /usr/bin/script.sh

Restart xinetd:

/etc/init.d/xinetd restart

EDIT: Don't forget

chmod +x /usr/bin/script.sh

Run script when someone telnet my server

2 Answers2