Subject: [dhcwg] [Errata Held for Document Update] RFC3495 (4128)

From: RFC Errata System <[email-masked]>
Date: Wed, 22 Apr 2015 08:31:19 -0700 (PDT)

The following errata report has been held for document update 
for RFC3495, "Dynamic Host Configuration Protocol (DHCP) Option for CableLabs Client Configuration". 

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You may review the report below and at:
http://www.rfc-editor.org/errata_search.php?rfc=3495&eid=4128

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Status: Held for Document Update
Type: Editorial

Reported by: Bernie Volz <[email-masked]>
Date Reported: 2014-10-10
Held by: Brian Haberman (IESG)

Section: 5.5.

Original Text
-------------
   The PacketCable architecture requires an MTA to authenticate itself
   to the TSP's network via the Kerberos protocol.  A Kerberos Realm
   name is required at the MTA to permit a DNS lookup for the address of
   the TSP's Kerberos Key Distribution Center (KDC) entity.

   The Kerberos Realm name MUST be encoded per the domain style realm
   name described in RFC 1510 [5].  This realm name MUST be all capital
   letters and conform to the syntax described in RFC 1035 [3] section
   3.1.  The sub-option is encoded as follows:

       Code   Len   Kerberos Realm Name
      +-----+-----+-----+-----+   +-----+
      |  6  |  n  |  k1 |  k2 |...|  kn |
      +-----+-----+-----+-----+   +-----+

Corrected Text
--------------
   The PacketCable architecture requires an MTA to authenticate itself
   to the TSP's network via the Kerberos protocol.  A Kerberos Realm
   name is required at the MTA to permit a DNS lookup for the address of
   the TSP's Kerberos Key Distribution Center (KDC) entity.

   The Kerberos Realm name MUST be use a domain style realm name
   described in RFC 1510 [5].  This realm name MUST be all capital
   letters and be encoded as described in RFC 1035 [3] section 3.1.
   The sub-option is encoded as follows:

       Code   Len   Kerberos Realm Name
      +-----+-----+-----+-----+   +-----+
      |  6  |  n  |  k1 |  k2 |...|  kn |
      +-----+-----+-----+-----+   +-----+

   Where k1...kn is the "DNS wire" encoded realm name (see RFC 3315,
   section 8). Thus, the realm "BASIC.1" is encoded as
   "RFCCORRECTED_TEXT5BASICRFCCORRECTED_TEXT11RFCCORRECTED_TEXT0".

Notes
-----
This text is not completely clear about how the realm name is to be encoded - as a 'string' or 'fqdn'.

RFC 1510 states:

   Kerberos realms are encoded as GeneralStrings. Realms shall not
   contain a character with the code 0 (the ASCII NUL).  Most realms
   will usually consist of several components separated by periods (.),
   in the style of Internet Domain Names, or separated by slashes (/) in
   the style of X.500 names.

And the reference to RFC 1035 section 3.1 is "conform to the syntax" which isn't the same as use this encoding - though I do agree that section 3.1 is mostly about "DNS wire encoding". It is just the use of "encoded" and "confirm to the syntax" combination that makes this unclear.

It is believed that the intended encoding is in DNS wire format. And, this should be clarified.

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RFC3495 (draft-ietf-dhc-packetcable-06)
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Title               : Dynamic Host Configuration Protocol (DHCP) Option for CableLabs Client Configuration
Publication Date    : March 2003
Author(s)           : B. Beser, P. Duffy, Ed.
Category            : PROPOSED STANDARD
Source              : Dynamic Host Configuration
Area                : Internet
Stream              : IETF
Verifying Party     : IESG