[TLS] [Technical Errata Reported] RFC8446 (5868)

RFC Errata System <rfc-editor@rfc-editor.org> Wed, 02 October 2019 11:17 UTC

To: ekr@rtfm.com, rdd@cert.org, kaduk@mit.edu, caw@heapingbits.net, joe@salowey.net, sean+ietf@sn3rd.com
From: RFC Errata System <rfc-editor@rfc-editor.org>
Cc: hkario@redhat.com, tls@ietf.org, rfc-editor@rfc-editor.org
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Message-Id: <20191002111715.2C349B817D2@rfc-editor.org>
Date: Wed, 02 Oct 2019 04:17:15 -0700
Archived-At: <https://mailarchive.ietf.org/arch/msg/tls/L6nkScsMiYAs3dGoehnhS14vhAw>
Subject: [TLS] [Technical Errata Reported] RFC8446 (5868)
Precedence: list

The following errata report has been submitted for RFC8446,
"The Transport Layer Security (TLS) Protocol Version 1.3".

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You may review the report below and at:
https://www.rfc-editor.org/errata/eid5868

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Type: Technical
Reported by: Hubert Kario <hkario@redhat.com>

Section: 4.2.3

Original Text
-------------
   ECDSA algorithms:  Indicates a signature algorithm using ECDSA
      [ECDSA], the corresponding curve as defined in ANSI X9.62 [ECDSA]
      and FIPS 186-4 [DSS], and the corresponding hash algorithm as
      defined in [SHS].  The signature is represented as a DER-encoded
      [X690] ECDSA-Sig-Value structure.

Corrected Text
--------------
   ECDSA algorithms:  Indicates a signature algorithm using ECDSA
      [ECDSA], the corresponding curve as defined in ANSI X9.62 [ECDSA]
      and FIPS 186-4 [DSS], and the corresponding hash algorithm as
      defined in [SHS].  The signature is represented as a DER-encoded
      [X690] ECDSA-Sig-Value structure as defined in [RFC4492].

Notes
-----
There is a possibility for confusion as the ECDSA-Sig-Value has two conflicting definitions in authoritative standards. TLS always used the following (see RFC4492):

   ECDSA-Sig-Value ::= SEQUENCE {
     r  INTEGER,
     s  INTEGER
   }

but the publicly accessible SECG SEC1 v2.0 (https://www.secg.org/sec1-v2.pdf) defines it like this:

ECDSA-Sig-Value ::= SEQUENCE {
 r INTEGER,
 s INTEGER,
 a INTEGER OPTIONAL,
 y CHOICE { b BOOLEAN, f FieldElement } OPTIONAL
}

I think using the RFC5480 in the Corrected Text would be cleaner than RFC4492, but the former is not an existing reference, so we would need to update section 12 also.

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RFC8446 (draft-ietf-tls-tls13-28)
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Title               : The Transport Layer Security (TLS) Protocol Version 1.3
Publication Date    : August 2018
Author(s)           : E. Rescorla
Category            : PROPOSED STANDARD
Source              : Transport Layer Security
Area                : Security
Stream              : IETF
Verifying Party     : IESG

[TLS] [Technical Errata Reported] RFC8446 (5868) RFC Errata System