Date: Fri, 18 Jan 2002 10:48:39 +0100 From: "Lajos Zaccomer (ETH)" <Lajos.Zaccomer@eth.ericsson.se> To: "'freebsd-questions@FreeBSD.org'" <freebsd-questions@FreeBSD.org> Subject: Telnet option negotiation Message-ID: <F005CD411D18D3119C8F00508B08748005CC79DD@ehubunt100.eth.ericsson.se>
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Hi FreeBSD experts,
I wrote a VERY simple telnet program that actually works as a Network Virtual Terminal. It is achieved by sending "WON'T XXX" to all "DO XXX" server requests. It should work according to RFC-854, page 4: "Since the NVT is what is left when no options are enabled, the DON'T and WON'T responses are guaranteed to leave the connection in a state which both ends can handle." It works with Unix, Linux, Windows, Cisco, but not with my FreeBSD: after a while it stops sending anything. This is the attempt trace:
Internet Protocol, Src Addr: 10.1.1.223 (10.1.1.223), Dst Addr: 10.1.1.222 (10.1.1.222)
Telnet
Command: Do Authentication Option
Internet Protocol, Src Addr: 10.1.1.222 (10.1.1.222), Dst Addr: 10.1.1.223 (10.1.1.223)
Telnet
Command: Do Echo
Command: Won't Authentication Option
Internet Protocol, Src Addr: 10.1.1.223 (10.1.1.223), Dst Addr: 10.1.1.222 (10.1.1.222)
Telnet
Command: Will Echo
Command: Will Encryption Option
Command: Do Terminal Type
Command: Do Terminal Speed
Command: Do X Display Location
Command: Do New Environment Option
Command: Do Environment Option
Internet Protocol, Src Addr: 10.1.1.222 (10.1.1.222), Dst Addr: 10.1.1.223 (10.1.1.223)
Telnet
Command: Won't Terminal Type
Command: Won't Terminal Speed
Command: Won't X Display Location
Command: Won't New Environment Option
Command: Won't Environment Option
Can you tell me why it does not work, and what can I do to make it work?
Thank you for all hints!
Regards,
Zacco
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<P><SPAN class=781022809-18012002>Hi FreeBSD experts,</SPAN></P>
<P><SPAN class=781022809-18012002>I wrote a VERY simple telnet program that
actually works as a Network Virtual Terminal. It is achieved by sending "WON'T
XXX" to all "DO XXX" server requests. It should work according to RFC-854, page
4: "Since the NVT is what is left when no options are enabled, the DON'T and
WON'T responses are guaranteed to leave the connection in a state which both
ends can handle." It works with Unix, Linux, Windows, Cisco, but not with my
FreeBSD: after a while it stops sending anything. This is the attempt
trace:</SPAN></P>
<P><SPAN class=781022809-18012002>Internet Protocol, Src Addr: 10.1.1.223
(10.1.1.223), Dst Addr: 10.1.1.222 (10.1.1.222)<BR>Telnet<BR>
Command: Do Authentication Option</SPAN></P><SPAN class=781022809-18012002>
<P><BR>Internet Protocol, Src Addr: 10.1.1.222 (10.1.1.222), Dst Addr:
10.1.1.223 (10.1.1.223)<BR>Telnet<BR> Command: Do
Echo<BR> Command: Won't Authentication Option</P>
<P><BR>Internet Protocol, Src Addr: 10.1.1.223 (10.1.1.223), Dst Addr:
10.1.1.222 (10.1.1.222)<BR>Telnet<BR> Command: Will
Echo<BR> Command: Will Encryption Option<BR>
Command: Do Terminal Type<BR> Command: Do Terminal
Speed<BR> Command: Do X Display Location<BR>
Command: Do New Environment Option<BR> Command: Do Environment
Option</P>
<P><BR>Internet Protocol, Src Addr: 10.1.1.222 (10.1.1.222), Dst Addr:
10.1.1.223 (10.1.1.223)<BR>Telnet<BR> Command: Won't Terminal
Type<BR> Command: Won't Terminal Speed<BR>
Command: Won't X Display Location<BR> Command: Won't New
Environment Option<BR> Command: Won't Environment Option</P>
<P><SPAN class=781022809-18012002>Can you tell me why it does not work, and what
can I do to make it work?</SPAN></P>
<P><SPAN class=781022809-18012002>Thank you for all hints!</SPAN></P>
<P><SPAN class=781022809-18012002>Regards,</SPAN></P>
<P><SPAN class=781022809-18012002>Zacco</SPAN></P>
<P><SPAN class=781022809-18012002></SPAN></SPAN> </P></BODY></HTML>
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