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Versions: (draft-badra-netconf-rfc5539bis) 00 01 02 03 04 05 06 07 08 09 10 RFC 7589

NETCONF Working Group                                           M. Badra
Internet-Draft                                          LIMOS Laboratory
Obsoletes: 5539 (if approved)                                  A. Luchuk
Intended status: Standards Track                           SNMP Research
Expires: April 25, 2013                                 J. Schoenwaelder
                                                Jacobs University Bremen
                                                        October 22, 2012


              NETCONF Over Transport Layer Security (TLS)
                    draft-ietf-netconf-rfc5539bis-01

Abstract

   The Network Configuration Protocol (NETCONF) provides mechanisms to
   install, manipulate, and delete the configuration of network devices.
   This document describes how to use the Transport Layer Security (TLS)
   protocol to secure NETCONF exchanges.  This document obsoletes RFC
   5539.

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 April 25, 2013.

Copyright Notice

   Copyright (c) 2012 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



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   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.


Table of Contents

   1.  Introduction . . . . . . . . . . . . . . . . . . . . . . . . .  3
     1.1.  Conventions Used in This Document  . . . . . . . . . . . .  3
   2.  NETCONF over TLS . . . . . . . . . . . . . . . . . . . . . . .  3
     2.1.  Connection Initiation  . . . . . . . . . . . . . . . . . .  3
     2.2.  Connection Closure . . . . . . . . . . . . . . . . . . . .  4
   3.  Endpoint Authentication, Identification and Authorization  . .  4
     3.1.  Server Identity  . . . . . . . . . . . . . . . . . . . . .  4
     3.2.  Client Identity  . . . . . . . . . . . . . . . . . . . . .  5
       3.2.1.  Deriving NETCONF Usernames From NETCONF Client
               Certificates . . . . . . . . . . . . . . . . . . . . .  5
       3.2.2.  Deriving NETCONF Usernames From PSK identities . . . .  7
       3.2.3.  Remote Configuration . . . . . . . . . . . . . . . . .  7
   4.  Security Considerations  . . . . . . . . . . . . . . . . . . . 14
   5.  IANA Considerations  . . . . . . . . . . . . . . . . . . . . . 15
   6.  Acknowledgements . . . . . . . . . . . . . . . . . . . . . . . 16
   7.  Contributor's Address  . . . . . . . . . . . . . . . . . . . . 16
   8.  References . . . . . . . . . . . . . . . . . . . . . . . . . . 16
     8.1.  Normative References . . . . . . . . . . . . . . . . . . . 16
     8.2.  Informative References . . . . . . . . . . . . . . . . . . 17
   Appendix A.  Change Log (to be removed by RFC Editor before
                publication)  . . . . . . . . . . . . . . . . . . . . 17
     A.1.  From draft-ietf-netconf-rfc5539bis-00 to
           draft-ietf-netconf-rfc5539bis-01 . . . . . . . . . . . . . 17
     A.2.  From draft-badra-netconf-rfc5539bis-02 to
           draft-ietf-netconf-rfc5539bis-00 . . . . . . . . . . . . . 17
   Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . . 17


















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1.  Introduction

   The NETCONF protocol [RFC6241] defines a mechanism through which a
   network device can be managed.  NETCONF is connection-oriented,
   requiring a persistent connection between peers.  This connection
   must provide integrity, confidentiality, peer authentication, and
   reliable, sequenced data delivery.

   This document defines "NETCONF over TLS", which includes support for
   certificate and pre-shared key (PSK)-based authentication and key
   derivation, utilizing the protected ciphersuite negotiation, mutual
   authentication, and key management capabilities of the TLS (Transport
   Layer Security) protocol, described in [RFC5246].

1.1.  Conventions Used in This Document

   The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT",
   "SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this
   document are to be interpreted as described in [RFC2119].


2.  NETCONF over TLS

   Since TLS is application-protocol-independent, NETCONF can operate on
   top of the TLS protocol transparently.  This document defines how
   NETCONF can be used within a TLS session.

2.1.  Connection Initiation

   The peer acting as the NETCONF client MUST also act as the TLS
   client.  The client actively opens the TLS connection and the server
   passively listens for the incoming TLS connection on the TCP port
   6513.  It MUST therefore send the TLS ClientHello message to begin
   the TLS handshake.  Once the TLS handshake has finished, the client
   and the server MAY begin to exchange NETCONF data.  In particular,
   the client will send complete XML documents to the server containing
   <rpc> elements, and the server will respond with complete XML
   documents containing <rpc-reply> elements.  The client MAY indicate
   interest in receiving event notifications from a server by creating a
   subscription to receive event notifications [RFC5277].  In this case,
   the server replies to indicate whether the subscription request was
   successful and, if it was successful, the server begins sending the
   event notifications to the client as the events occur within the
   system.

   All NETCONF messages MUST be sent as TLS "application data".  It is
   possible that multiple NETCONF messages be contained in one TLS
   record, or that a NETCONF message be transferred in multiple TLS



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   records.

   The previous version [RFC5539] of this document used the same framing
   sequence defined in [RFC6242], under the assumption that it could not
   be found in well-formed XML documents.  However, this assumption is
   not correct [RFC6242].  In order to solve this problem, and at the
   same time be compatible with existing implementations, this document
   uses the framing protocol defined in [RFC6242] as following:

   The <hello> message MUST be followed by the character sequence
   ]]>]]>.  Upon reception of the <hello> message, the receiving peer's
   TLS Transport layer conceptually passes the <hello> message to the
   Messages layer.  If the :base:1.1 capability is advertised by both
   peers, the chunked framing mechanism defined in Section 4.2 of
   [RFC6242] is used for the remainder of the NETCONF session.
   Otherwise, the old end-of-message-based mechanism (see Section 4.3 of
   [RFC6242]) is used.

   Implementation of the protocol specified in this document MAY
   implement any TLS cipher suite that provides mutual authentication
   [RFC5246].

   Implementations MUST support TLS 1.2 [RFC5246] and are REQUIRED to
   support the mandatory-to-implement cipher suite, which is
   TLS_RSA_WITH_AES_128_CBC_SHA.  This document is assumed to apply to
   future versions of TLS; in which case, the mandatory-to-implement
   cipher suite for the implemented version MUST be supported.

2.2.  Connection Closure

   Exiting NETCONF is accomplished using the <close-session> operation.
   A NETCONF server will process NETCONF messages from the NETCONF
   client in the order in which they are received.  When the NETCONF
   server processes a <close-session> operation, the NETCONF server
   SHALL respond and close the TLS session channel.  The NETCONF server
   MUST NOT process any NETCONF messages received after the <close-
   session> operation.  The TLS session is closed as described in
   [RFC6242] Section 7.2.1.


3.  Endpoint Authentication, Identification and Authorization

3.1.  Server Identity

   If the server's presented certificate has passed certification path
   validation [RFC5280] to a configured trust anchor, the client MUST
   carefully examine the certificate presented by the server to
   determine if it meets the client's expectations.  Particularly, the



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   client MUST check its understanding of the server hostname against
   the server's identity as presented in the server Certificate message,
   in order to prevent man- in-the-middle attacks.

   Matching is performed according to the rules and guidelines defined
   in [RFC6125].

   If the match fails, the client MUST either ask for explicit user
   confirmation or terminate the connection and indicate the server's
   identity is suspect.

   Additionally, clients MUST verify the binding between the identity of
   the servers to which they connect and the public keys presented by
   those servers.  Clients SHOULD implement the algorithm in Section 6
   of [RFC5280] for general certificate validation, but MAY supplement
   that algorithm with other validation methods that achieve equivalent
   levels of verification (such as comparing the server certificate
   against a local store of already-verified certificates and identity
   bindings).

   If the client has external information as to the expected identity of
   the server, the hostname check MAY be omitted.

3.2.  Client Identity

   The server MUST verify the identity of the client to ensure that the
   incoming client request is legitimate before the NETCONF session is
   started.

   The NETCONF protocol [RFC6241] requires that the transport protocol's
   authentication process MUST result in an authenticated client
   identity whose permissions are known to the server.  The
   authenticated identity of a client is commonly referred to as the
   NETCONF username.

   The username provided by the TLS implementation will be made
   available to the NETCONF message layer as the NETCONF username
   without modification.  If the username does not comply to the NETCONF
   requirements on usernames [RFC6241], i.e., the username is not
   representable in XML, the TLS session MUST be dropped.

   Algorithms for mapping certificates or PSK identities (sent by the
   client) to NETCONF usernames are described below.

3.2.1.  Deriving NETCONF Usernames From NETCONF Client Certificates

   The algorithm for deriving NETCONF usernames from TLS certificates is
   patterned after the algorithm for deriving tmSecurityNames from TLS



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   certificates specified in Transport Layer Security (TLS) Transport
   Model for the Simple Network Management Protocol (SNMP) [RFC6353].
   The NETCONF server MUST implement the algorithms for deriving NETCONF
   usernames from presented certificates that are documented in the
   ietf-netconf-tls YANG module, defined in Section 3.2.3.  This YANG
   module lets the NETCONF security administrator configure how the
   NETCONF server derives NETCONF usernames from presented certificates.
    It also lets different certificate-to-username derivation algorithms
   be used for different certificates.

   When a NETCONF server accepts a TLS connection from a NETCONF client,
   the NETCONF server attempts to derive a NETCONF username from the
   certificate presented by the NETCONF client.  If the NETCONF server
   cannot derive a valid NETCONF username from the client's presented
   certificate, then the NETCONF server MUST close the TLS connection,
   and MUST NOT accept NETCONF messages over it.   The NETCONF server
   uses one of the following algorithms to produce a NETCONF username
   from the certificate presented by the NETCONF client:

   o  Map a certificate directly to a specified, pre-configured, NETCONF
      username;

   o  Extract the subjectAltName's rfc822Name from the certificate, then
      use the extracted rfc822Name as the NETCONF username;

   o  Extract the subjectAltName's dnsName from the certificate, then
      use the extracted dnsName as the NETCONF username;

   o  Extract the subjectAltName's iPAddress from the certificate, then
      use the extracted iPAddress as the NETCONF username;

   o  Examine the subjectAltName's rfc822Name, dnsName, and iPAddress
      fields in a pre-defined order.  Return the value from the first
      subjectAltName field that is examined, defined, and populated with
      a non-empty value.  If no subjectAltName field of a specific type
      is defined, then the examination skips that field and proceeds to
      examine the next field type.  If a subjectAltName field is
      defined, but the value is not populated, or is populated by an
      empty value, then the examination skips that field and proceeds to
      examine the next field type.

   The NETCONF server MUST implement all of these algorithms, and allow
   the deployer to choose the algorithm used.  The cert-map list in the
   ietf-netconf-tls YANG module specifies how a NETCONF server
   transforms a certificate into a NETCONF username.

   If the fingerprint of locally held copy of a trusted CA certificate
   is configured in the cert-map list in the ietf-netconf-tls YANG



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   module, and that CA certificate is used to validate the certificate
   presented by the client, then the NETCONF server uses that cert-map
   list entry to produce the NETCONF username.  This allows multiple
   client certificates (all signed by the same trusted CA certificate)
   to be mapped to a NETCONF username by a single entry in the cert-map
   list.

3.2.2.  Deriving NETCONF Usernames From PSK identities

   Implementations MAY optionally support TLS Pre-Shared Key (PSK)
   authentication [RFC4279].  RFC4279 describes pre-shared key
   ciphersuites for TLS.  The description of the psk-maps container in
   the ietf-netconf-tls YANG module, defined in section 3.2.3, specifies
   how a NETCONF server transforms a TLS pre-shared key into a NETCONF
   username.

3.2.3.  Remote Configuration

   The ietf-netconf-tls YANG module defines objects for remotely
   configuring the mapping of TLS certficates and of PSK Identities to
   NETCONF usernames.



module ietf-netconf-tls {

 namespace "urn:ietf:params:xml:ns:yang:ietf-netconf-tls";

 prefix "nctls";

 import ietf-yang-types {
  prefix yang;
 }

 import ietf-netconf-acm {
  prefix nacm;
 }

 organization
  "IETF NETCONF (Network Configuration) Working Group";

 contact
  "WG Web:   <http://tools.ietf.org/wg/netconf/>
   WG List:  <mailto:netconf@ietf.org>

   WG Chair: Mehmet Ersue
             <mailto:mehmet.ersue@nsn.com>




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   WG Chair: Bert Wijnen
             <mailto:bertietf@bwijnen.net>

   Editor:   Mohamad Badra
             <mailto:mbadra@gmail.com>";

 description
  "This module applies to NETCONF over TLS.  It specifies how NETCONF
   servers transform X.509 certificates presented by clients into
   NETCONF usernames.  It also specifies how NETCONF servers transform
   pre-shared TLS keys into NETCONF usernames.

   The cert-maps container in this YANG module is patterned after parts
   of the SNMP-TLS-TM-MIB defined in RFC 6353.  Much of the description
   text has been copied directly from the SNMP-TLS-TM-MIB, and modified
   as necessary.

   Copyright (c) 2012 IETF Trust and the persons identified as
   authors of the code. All rights reserved.

   Redistribution and use in source and binary forms, with or
   without modification, is permitted pursuant to, and subject
   to the license terms contained in, the Simplified BSD
   License set forth in Section 4.c of the IETF Trust's
   Legal Provisions Relating to IETF Documents
   (http://trustee.ietf.org/license-info).

   This version of this YANG module is part of RFC XXXX; see
   the RFC itself for full legal notices.";
 // RFC Ed.: replace XXXX with actual RFC number and
 // remove this note

 // RFC Ed.: please update the date to the date of publication

 revision "2012-02-13" {
  description
    "Initial version";
  reference
    "RFC XXXX: NETCONF over Transport Layer Security (TLS)";
 }

 feature map-certificates {
  description
    "The map-certificates feature indicates that the server implements
     mapping X.509 certificates to NETCONF user names.";
 }

 feature map-pre-shared-keys {



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  description
    "The map-pre-shared-keys feature indicates that the server
     implements mapping TLS pre-shared keys to NETCONF user names.";

 }

 typedef tls-fingerprint-type {
  type string {
    pattern '([0-9a-fA-F]){2}(:([0-9a-fA-F]){2})*';
  }
  description
    "A cryptographic signature (fingerprint) value that can be used to
     uniquely reference other data of potentially arbitrary length.";
 }


 container netconf-config {

  container tls {

 //
 //  Objects related to deriving NETCONF usernames from X.509
 //  certificates.
 //

   container cert-maps {
    if-feature map-certificates;
    config true;

    description
      "The cert-maps container is used by a NETCONF server to map the
       NETCONF client's presented X.509 certificate to a NETCONF username.

       On an incoming TLS connection, the client's presented certificate
       MUST either be validated based on an established trust anchor, or
       it MUST directly match a fingerprint in the 'cert-map' list.  This
       module does not provide any mechanisms for configuring the
       trust anchors; the transfer of any needed trusted certificates
       for certificate chain validation is expected to occur through an
       out-of-band transfer.

       Once the certificate has been found acceptable (either by
       certificate chain validation or directly matching a fingerprint
       in the cert-map list), the cert-map list is consulted to determine
       the appropriate NETCONF username to associate with the remote
       connection.  This is done by considering each cert-map list entry
       in order.  The cert-map entry's fingerprint determines whether the
       list entry is a match for the incoming connection:



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           1) If the cert-map list entry's fingerprint value matches that
              of the presented certificate, then consider the list entry
              as a successful match.

           2) If the cert-map list entry's fingerprint value matches that
              of a locally held copy of a trusted CA certificate, and
              that CA certificate was part of the CA certificate chain
              to the presented certificate, then consider the list entry
              as a successful match.

       Once a matching cert-map list entry has been found, the NETCONF
       server uses the map-type list to determine how the NETCONF username
       associated with the session should be determined.  See the map-
       type leaf's description for details on determining the NETCONF
       username value.  If it is impossible to determine a NETCONF
       username from the cert-map list entry's data combined with the data
       presented in the certificate, then additional cert-map list entries
       MUST be searched looking for another potential match.  If a resulting
       NETCONF username mapped from a given cert-map list entry is not
       compatible with the needed requirements of a NETCONF username,
       then it MUST be considered an invalid match and additional cert-map
       list entries MUST be searched looking for another potential match.

       If no matching and valid cert-map list entry can be found, then the
       NETCONF server MUST close the connection, and MUST NOT accept
       NETCONF messages over it.

       Security administrators are encouraged to make use of certificates
       with subjectAltName fields that can be used as NETCONF usernames
       so that a single root CA certificate can allow all child
       certificate's subjectAltName to map directly to a NETCONF
       usernames via a 1:1 transformation.";

    list cert-map {
      key "key";
      ordered-by user;
      description
        "A single list entry that specifies a mapping for an incoming
        TLS certificate to a NETCONF username.";

      leaf key {
        type string;
        nacm:default-deny-all;
        description
          "The key associated with the cert-map list.";
      }

      container fingerprint {



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        choice algorithm-and-hash {
          mandatory true;
          leaf md5 {
            type tls-fingerprint-type;
          }
          leaf sha1 {
            type tls-fingerprint-type;
          }
          leaf sha224 {
            type tls-fingerprint-type;
          }
          leaf sha256 {
            type tls-fingerprint-type;
          }
          leaf sha384 {
            type tls-fingerprint-type;
          }
          leaf sha512 {
            type tls-fingerprint-type;
          }
          description
            "Specifies the signature algorithm and cryptographic
             signature (fingerprint) used to identify an X.509
             certificate.

             Implementations of this YANG module MAY, but are not
             required to, implement all of these cryptographic signature
             algorithms.  Implementations of this YANG module MUST
             implement at least one of these cryptographic signature
             algorithms.

             The available choices may be extended in the future as
             stronger cryptographic signature algorithms become
             available and are deemed necessary.";

          reference
            "RFC 5246: The Transport Layer Security (TLS) Protocol
             Version 1.2; Section 7.4.1.4.1,  Signature Algorithms";
        }  // choice algorithm-and-hash
      }    // container fingerprint

      choice map-type {
        leaf specified {
          type nacm:user-name-type;
          description
            "Directly specifies the NETCONF username to be used for this
             certificate.";
        }



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        leaf-list from-certificate {
          ordered-by user;
          type enumeration {
            enum rfc822Name {
              description
                "Maps a subjectAltName's rfc822Name to a NETCONF username.
                 The local part of the rfc822Name is passed unaltered but
                 the domain-part of the name MUST be passed in lowercase.
                 This mapping results in a 1:1 correspondence between
                 equivalent subjectAltName rfc822Name values and NETCONF
                 username values except that the domain-part of the name
                 MUST be passed in lowercase.

                 Example rfc822Name Field:  FooBar@Example.COM
                 is mapped to NETCONF username: FooBar@example.com.";
            }
            enum dNSName {
              description
                "Maps a subjectAltName's dNSName to a NETCONF username after
                 first converting it to all lowercase (RFC 5280 does not
                 specify converting to lowercase so this involves an extra
                 step).  This mapping results in a 1:1 correspondence between
                 subjectAltName dNSName values and the NETCONF username
                 values.

                 reference:  RFC 5280 - Internet X.509 Public Key
                             Infrastructure Certificate and Certificate
                             Revocation List (CRL) Profile.";
            }
            enum ipAddress {
              description
                "Maps a subjectAltName's iPAddress to a NETCONF username by
                 transforming the binary encoded address as follows:

                 1) for IPv4, the value is converted into a
                    decimal-dotted quad address (e.g., '192.0.2.1').

                 2) for IPv6 addresses, the value is converted into a
                    32-character all lowercase hexadecimal string
                    without any colon separators.

                    This mapping results in a 1:1 correspondence between
                    subjectAltName iPAddress values and the NETCONF username
                    values.";
            }
          }
        }   // leaf-list from-certificate




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        description
          "Specifies the algorithm for deriving a NETCONF username from
           a certificate.  If a mapping succeeds, then it will return a
           NETCONF username.

           If the resulting mapped value is not compatible with the
           needed requirements of a NETCONF username, then subsequent
           cert-map list entries MUST be searched for additional
           matches to look for a mapping that succeeds.";

      }   // choice map-type
    }     // list cert-map
   }      // container cert-maps


 //
 //  Objects related to deriving NETCONF usernames from TLS pre-shared
 //  keys.
 //

   container psk-maps {
    if-feature map-pre-shared-keys;

    description
      "During the TLS Handshake, the client indicates which key to use
       by including a PSK identity in the TLS ClientKeyExchange message.
       On the server side, this PSK identity is used to look up an entry
       in the psk-map list.  If such an entry is found, and the pre-shared
       keys match, then the client is authenticated.  The server uses the
       value from the user-name leaf in the psk-map list as the NETCONF
       username.  If the server cannot find an entry in the psk-map list,
       or if the pre-shared keys do not match, then the server terminates
       the connection.  For details on how the PSK identity MAY be encoded
       in UTF-8, see section 5.1. of RFC 4279.";

    reference
      "RFC 4279: Pre-Shared Key Ciphersuites for Transport Layer
                 Security (TLS)";

    list psk-map {
      key psk-identity;

      leaf psk-identity {
        type string;
        description
          "The PSK identity encoded as a UTF-8 string.";
        reference
          "RFC 4279: Pre-Shared Key Ciphersuites for Transport Layer



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                    Security (TLS)";
      }

      leaf user-name {
        type nacm:user-name-type;
        mandatory true;
        description
         "The NETCONF username associated with this PSK identity.";
      }

      leaf valid-not-before {
        type yang:date-and-time;
        description
          "This PSK identity is not valid before the given data
           and time.";
      }

      leaf valid-not-after {
        type yang:date-and-time;
        description
          "This PSK identity is not valid before the given date
           and time.";
      }

      leaf key {
        type string {
          pattern '([0-9a-fA-F]){2}(:([0-9a-fA-F]){2})*';
        }
        nacm:default-deny-all;
        description
          "The key associated with the PSK identity";
      }
    }   // list psk-map
   }    // container psk-maps

  }     // container tls
 }      // container netconf-config
}




4.  Security Considerations

   The security considerations described throughout [RFC5246] and
   [RFC6241] apply here as well.

   This document in its current version does not support third-party



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   authentication (e.g., backend Authentication, Authorization, and
   Accounting (AAA) servers) due to the fact that TLS does not specify
   this way of authentication and that NETCONF depends on the transport
   protocol for the authentication service.  If third-party
   authentication is needed, SSH transport can be used.

   An attacker might be able to inject arbitrary NETCONF messages via
   some application that does not carefully check exchanged messages.
   When the :base:1.1 capability is not advertised by both peers, an
   attacker might be able to deliberately insert the delimiter sequence
   ]]>]]> in a NETCONF message to create a DoS attack.  If the :base:1.1
   capability is not advertised by both peers, applications and NETCONF
   APIs MUST ensure that the delimiter sequence ]]>]]> never appears in
   NETCONF messages; otherwise, those messages can be dropped, garbled,
   or misinterpreted.  More specifically, if the delimiter sequence is
   found in a NETCONF message by the sender side, a robust
   implementation of this document SHOULD warn the user that illegal
   characters have been discovered.  If the delimiter sequence is found
   in a NETCONF message by the receiver side (including any XML
   attribute values, XML comments, or processing instructions), a robust
   implementation of this document MUST silently discard the message
   without further processing and then stop the NETCONF session.

   Finally, this document does not introduce any new security
   considerations compared to [RFC6242].


5.  IANA Considerations

   Based on the previous version of this document, RFC 5539, IANA has
   assigned a TCP port number (6513) in the "Registered Port Numbers"
   range with the name "netconf-tls".  This port will be the default
   port for NETCONF over TLS, as defined in this document.


      Registration Contact:  Mohamad Badra, mbadra@gmail.com.
      Transport Protocol:  TCP.
      Port Number:  6513
      Broadcast, Multicast or Anycast: No.
      Port Name:  netconf-tls.
      Service Name: netconf.
      Reference: RFC 5539









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6.  Acknowledgements

   A significant amount of the text in Section 3 was lifted from
   [RFC4642].

   The author would like to acknowledge David Harrington, Miao Fuyou,
   Eric Rescorla, Simon Josefsson, Olivier Coupelon, Alfred Hoenes, and
   the NETCONF mailing list members for their comments on the document.
   The author also appreciates Bert Wijnen, Mehmet Ersue, and Dan
   Romascanu for their efforts on issues resolving discussion; and
   Charlie Kaufman, Pasi Eronen, and Tim Polk for the thorough review of
   previous versions of this document.


7.  Contributor's Address

   Ibrahim Hajjeh
   Ineovation
   France

   EMail: ibrahim.hajjeh@ineovation.fr


   Martin Bjorklund
   Tail-f Systems

   Email: mbj@tail-f.com



8.  References

8.1.  Normative References

   [RFC2119]  Bradner, S., "Key words for use in RFCs to Indicate
              Requirement Levels", BCP 14, RFC 2119, March 1997.

   [RFC4279]  Eronen, P. and H. Tschofenig, "Pre-Shared Key Ciphersuites
              for Transport Layer Security (TLS)", RFC 4279,
              December 2005.

   [RFC5246]  Dierks, T. and E. Rescorla, "The Transport Layer Security
              (TLS) Protocol Version 1.2", RFC 5246, August 2008.

   [RFC5280]  Cooper, D., Santesson, S., Farrell, S., Boeyen, S.,
              Housley, R., and W. Polk, "Internet X.509 Public Key
              Infrastructure Certificate and Certificate Revocation List
              (CRL) Profile", RFC 5280, May 2008.



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   [RFC6125]  Saint-Andre, P. and J. Hodges, "Representation and
              Verification of Domain-Based Application Service Identity
              within Internet Public Key Infrastructure Using X.509
              (PKIX) Certificates in the Context of Transport Layer
              Security (TLS)", RFC 6125, March 2011.

   [RFC6242]  Wasserman, M., "Using the NETCONF Protocol over Secure
              Shell (SSH)", RFC 6242, June 2011.

   [RFC6353]  Hardaker, W., "Transport Layer Security (TLS) Transport
              Model for the Simple Network Management Protocol (SNMP)",
              RFC 6353, July 2011.

8.2.  Informative References

   [RFC4642]  Murchison, K., Vinocur, J., and C. Newman, "Using
              Transport Layer Security (TLS) with Network News Transfer
              Protocol (NNTP)", RFC 4642, October 2006.

   [RFC5277]  Chisholm, S. and H. Trevino, "NETCONF Event
              Notifications", RFC 5277, July 2008.

   [RFC5539]  Badra, M., "NETCONF over Transport Layer Security (TLS)",
              RFC 5539, May 2009.

   [RFC6241]  Enns, R., Bjorklund, M., Schoenwaelder, J., and A.
              Bierman, "Network Configuration Protocol (NETCONF)",
              RFC 6241, June 2011.


Appendix A.  Change Log (to be removed by RFC Editor before publication)

A.1.  From draft-ietf-netconf-rfc5539bis-00 to
      draft-ietf-netconf-rfc5539bis-01

   o  Update Section 3.2 and address some issues raised during WGLC

A.2.  From draft-badra-netconf-rfc5539bis-02 to
      draft-ietf-netconf-rfc5539bis-00

   o  Remove the reference to BEEP

   o  Rename host-part to domain-part in the description of RFC822.








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Authors' Addresses

   Mohamad Badra
   LIMOS Laboratory

   Email: mbadra@gmail.com


   Alan Luchuk
   SNMP Research

   Email: luchuk@snmp.com


   Juergen Schoenwaelder
   Jacobs University Bremen

   Email: j.schoenwaelder@jacobs-university.de

































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