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IUTF8 Terminal Mode in Secure Shell (SSH)
draft-sgtatham-secsh-iutf8-01

The information below is for an old version of the document.
Document Type
This is an older version of an Internet-Draft that was ultimately published as RFC 8160.
Authors Simon Tatham , Darren Tucker
Last updated 2016-06-20 (Latest revision 2016-05-03)
RFC stream Internet Engineering Task Force (IETF)
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IESG IESG state Became RFC 8160 (Proposed Standard)
Consensus boilerplate Yes
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Responsible AD Kathleen Moriarty
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draft-sgtatham-secsh-iutf8-01
Network Working Group                                          S. Tatham
Internet-Draft                                                     PuTTY
Intended status: Standards Track                               D. Tucker
Expires: November 4, 2016                                        OpenSSH
                                                             May 3, 2016

               IUTF8 Terminal Mode in Secure Shell (SSH)
                     draft-sgtatham-secsh-iutf8-01

Abstract

   This document specifies a value for the widely used IUTF8 bit in the
   Secure Shell terminal modes encoding.

Status of This Memo

   This Internet-Draft is submitted in full conformance with the
   provisions of BCP 78 and BCP 79.

   Internet-Drafts are working documents of the Internet Engineering
   Task Force (IETF).  Note that other groups may also distribute
   working documents as Internet-Drafts.  The list of current Internet-
   Drafts is at http://datatracker.ietf.org/drafts/current/.

   Internet-Drafts are draft documents valid for a maximum of six months
   and may be updated, replaced, or obsoleted by other documents at any
   time.  It is inappropriate to use Internet-Drafts as reference
   material or to cite them other than as "work in progress."

   This Internet-Draft will expire on November 4, 2016.

Copyright Notice

   Copyright (c) 2016 IETF Trust and the persons identified as the
   document authors.  All rights reserved.

   This document is subject to BCP 78 and the IETF Trust's Legal
   Provisions Relating to IETF Documents
   (http://trustee.ietf.org/license-info) in effect on the date of
   publication of this document.  Please review these documents
   carefully, as they describe your rights and restrictions with respect
   to this document.  Code Components extracted from this document must
   include Simplified BSD License text as described in Section 4.e of
   the Trust Legal Provisions and are provided without warranty as
   described in the Simplified BSD License.

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Table of Contents

   1.  Introduction  . . . . . . . . . . . . . . . . . . . . . . . .   2
   2.  Conventions Used in this Document . . . . . . . . . . . . . .   2
   3.  New terminal mode . . . . . . . . . . . . . . . . . . . . . .   2
   4.  IANA Considerations . . . . . . . . . . . . . . . . . . . . .   3
   5.  Security Considerations . . . . . . . . . . . . . . . . . . .   3
   6.  Acknowledgements  . . . . . . . . . . . . . . . . . . . . . .   3
   7.  References  . . . . . . . . . . . . . . . . . . . . . . . . .   3
     7.1.  Normative References  . . . . . . . . . . . . . . . . . .   3
     7.2.  Informative References  . . . . . . . . . . . . . . . . .   3
   Authors' Addresses  . . . . . . . . . . . . . . . . . . . . . . .   4

1.  Introduction

   The Secure Shell (SSH) connection protocol [RFC4254] provides an
   encoding for terminal modes, used in the "pty-req" channel request
   type.

   A commonly used terminal mode is IUTF8, which indicates that the
   terminal driver should assume that terminal I/O uses the UTF-8
   character encoding.  This is typically used by the kernel's terminal
   driver on the server to decide how many bytes of input to treat as a
   single logical character during line editing.

   SSH currently does not provide an encoding for IUTF8.  This document
   specifies one.

2.  Conventions Used in this Document

   The key phrases "SHOULD" and "MAY" in this document are to be
   interpreted as described in [RFC2119].

3.  New terminal mode

   The opcode value 42 is defined for the IUTF8 terminal mode.

   As [RFC4254] section 8 specifies for all opcodes in the range 1 to
   159, it is therefore followed by a single uint32 argument.  The value
   0 indicates that the IUTF8 mode is disabled, and the value 1
   indicates that it is enabled.

   As with all other encoded terminal modes, the client SHOULD transmit
   a value for this mode if it knows about one, and the server MAY
   ignore it.

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4.  IANA Considerations

   This document augments the "Encoding of Terminal Modes" list in
   section 8 of [RFC4254].

   IANA is requested to update the SSH encoded terminal modes registry
   with the following additional entry:

   opcode  mnemonic       description
   ------  --------       -----------
   42      IUTF8          Terminal input and output is assumed to be
                           encoded in UTF-8.

                                 Figure 1

5.  Security Considerations

   The security considerations of [RFC4254] apply.  This additional
   terminal mode encoding is believed to have no security implications
   differing from the existing set of encoded terminal modes.

6.  Acknowledgements

   The authors are indebted to Colin Watson for originally suggesting
   this terminal mode in 2006, and David Madore and Jakub Jelen for
   prior implementation efforts.

   This document was written using the xml2rfc tool described in
   [RFC2629].

7.  References

7.1.  Normative References

   [RFC2119]  Bradner, S., "Key words for use in RFCs to Indicate
              Requirement Levels", BCP 14, RFC 2119,
              DOI 10.17487/RFC2119, March 1997,
              <http://www.rfc-editor.org/info/rfc2119>.

   [RFC4254]  Ylonen, T. and C. Lonvick, Ed., "The Secure Shell (SSH)
              Connection Protocol", RFC 4254, DOI 10.17487/RFC4254,
              January 2006, <http://www.rfc-editor.org/info/rfc4254>.

7.2.  Informative References

   [RFC2629]  Rose, M., "Writing I-Ds and RFCs using XML", RFC 2629,
              DOI 10.17487/RFC2629, June 1999,
              <http://www.rfc-editor.org/info/rfc2629>.

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Authors' Addresses

   Simon Tatham
   PuTTY

   Email: anakin@pobox.com

   Darren Tucker
   OpenSSH

   Email: dtucker@openssh.com

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