>My point is where did you get the value 129, and who
>authorized you to use it?

This is just a number which we are using for the time being. Our Telnet
Server and Telnet Clients which have implemented this type are configurable
to use any other number for this type. This will allow us to use any IETF
assigned number in future.

> I would be interested in seeing a write-up of your
> USE_GSS_ENCRYPTION.
> I wonder how you are using GSSAPI for ENCRYPTION without
> using it for authentication.

We are using GSSAPI for Kerberos Authentication and Encryption. Our Telnet
server always uses GSSAPI to talk to Kerberos. Our Telnet server is able to
accept either raw AP-Request message (no GSS framing) or with GSS framing.
When the incoming token has GSS framing, the outgoing reply token also has
GSS framing. This allows the MIT style Telnet clients (no GSS framing) to
connect to our Telnet server.

In terms of Telnet negotiations, the negotiations when USE_GSS_ENCRYPTION is
used are identical to the case when the DES_CFB64 is negotiated between the
client and the server. There is no IV associated with the
USE_GSS_ENCRYPTION.

In our case, our Telnet client is runs on the Win2K machine and acquires
service ticket for the remote host using SSPI. This token has GSS framing
and it may also include forwarded credentials. Our Telnet server uses GSSAPI
( who calls Kerberos) to authenticate the client using this token. The
client can use encryption by utilizing SSPI provided EncryptMessage
(GSS_WRAP) calls.

This has allowed the client to work without needing any KRB5 library and we
are able to use either DES or RC4 for encryption.

Salil


"Jeffrey Altman" <[EMAIL PROTECTED]> wrote in message
9v316h$7d7$[EMAIL PROTECTED]">news:9v316h$7d7$[EMAIL PROTECTED]...
> I know the text of RFC 2946 very well.  I am one of the authors.
>
> My point is where did you get the value 129, and who authorized
> you to use it?
>
> These are internet standards using shared address spaces.  You can't
> just choose numbers out of a hat.  I have already had to deal with
> collisions in the name space because people randomly decided to use
> arbitrary values without registering them with the appropriate
> organizations.
>
> I would be interested in seeing a write-up of your USE_GSS_ENCRYPTION.
> I wonder how you are using GSSAPI for ENCRYPTION without using it
> for authentication.
>
>
> In article <9v2rfb$rbk$[EMAIL PROTECTED]>,
> Salil Dangi <[EMAIL PROTECTED]> wrote:
> : > Just wondering:
> : >  . where did you get the Telnet Encryption Option ENCTYPE number from?
> : >  Jeffrey Altman * Sr.Software Designer      C-Kermit 8.0 Beta
available
> :
> : RFC 2946 defines available Encryption types.
> : We have implemented a variant and called it USS_GSS_ENCRYPTION
> : and currently using a value of 129.
> :
> : Salil
> :
> : RFC 2946
> :    ENCRYPT         38
> :        Encryption Commands
> :        IS               0
> :        SUPPORT          1
> :        REPLY            2
> :        START            3
> :        END              4
> :        REQUEST-START    5
> :        REQUEST-END      6
> :        ENC_KEYID        7
> :        DEC_KEYID        8
> :        Encryption Types
> :        NULL             0
> :        DES_CFB64        1
> :        DES_OFB64        2
> :        DES3_CFB64       3
> :        DES3_OFB64       4
> :        CAST5_40_CFB64   8
> :        CAST5_40_OFB64   9
> :        CAST128_CFB64   10
> :        CAST128_OFB64   11
> :
> :
> :
>
>
>  Jeffrey Altman * Sr.Software Designer      C-Kermit 8.0 Beta available
>  The Kermit Project @ Columbia University   includes Secure Telnet and FTP
>  http://www.kermit-project.org/             using Kerberos, SRP, and
>  [EMAIL PROTECTED]          OpenSSL.  SSH soon to follow.


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