telnet notes

Telnet is a wonderful legacy, now totally insecure and replaced by SSH etc. but there are plenty of interesting things to learn: means press the enter/return key NOTE that for http the screen will be blank, BLIND typing =) UPPERCASE FOR COMMANDS - OR FOR EVERYTHING

telnet www.yahoo.com 80 HEAD / HTTP/1.1 HOST:WWW.YAHOO.COM

telnet www.yahoo.com 80 GET / HTTP/1.1 HOST:WWW.YAHOO.COM

telnet ipchicken.com 80 //gets your external ip address! =) GET / HTTP/1.1 HOST:IPCHICKEN.COM

telnet pop.mail.yahoo.com 110 user username pass password stat //+ok #of msgs & #totalbytes list //msg # and msg size retr 1 //retrieve msg1 (show) top 1 5 //optional cmd, lists the header for msg 1 & first 5 lines dele 1 //marks a msg for deletion when you quit (disconnect shouldn't delete) rset 1 //resets marks for msgs for deletion (don't delete) quit

from the microsoft cmd prompt telnet ? //help with commands set ? //help with what options you can set set localecho o 192.168.1.4 25 //open a connection to cpu w/ ip address on port 25 ehlo domain.com //shows the info of that domain mail from:test@test.com //create an email from test rcpt to:user@faraway.com //recipient should be user@faraway.com

550 5.7.1 Unable to relay for ... //not an open relay (but emails can still be sent to local recipients)

telnet mail.YourServer.com 25 ehlo mail from:john@domain.com rcpt to:john@OtherDomain.com data Telnet is fun! How does this look? Backspace doesn't work properly. . quit

EXAMPLE: IT WILL LOOK LIKE THIS

220 mailserver 959 ready at Fri, 25 Jan 2008 11:43:22 +0000 ehlo 250-mailserver Hello [127.0.0.1] 250-TURN 250-SIZE 250-ETRN 250-DSN 250-ENHANCEDSTATUSCODES 250-8bitmime 250-BINARYMIME 250-VRFY 250-X-EXPS GSSAPI NTLM LOGIN 250-X-EXPS=LOGIN 250-AUTH GSSAPI NTLM LOGIN 250-AUTH=LOGIN 250-X-LINK2STATE 250 OK

mail from:john@domain.com 250 2.1.0 john@domain.com.com....Sender OK rcpt to: test@domain.com 250 2.1.5 test@domain.com data //sometimes should be DATA? 354 Start mail input; end with . Telnet is fun! How does this look? Backspace doesn't work properly.

.

250 2.6.0 Queued mail for delivery

At the very end, credit goes to: http://usertools.plus.net/tutorials/id/21 http://www.ietf.org/rfc/rfc1939.txt //pop3