Subject: [Curdle] Roman Danyliw's Yes on draft-ietf-curdle-ssh-kex-sha2-19: (with COMMENT)

From: Roman Danyliw via Datatracker <[email-masked]>
Date: Tue, 13 Jul 2021 18:51:56 -0700

Roman Danyliw has entered the following ballot position for
draft-ietf-curdle-ssh-kex-sha2-19: Yes

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COMMENT:
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Thank you for this helpful, prescriptive guidance.

Thank you to Mališa Vučinić for the multiple SECDIR reviews.

** Table 1, 2, 4, 5.  Cite the basis of the estimated security strengths.  A
few pointers to jump start this process:

-- Table 1: NIST 800-57Part1R5, Section 5.6.1.1
(https://nvlpubs.nist.gov/nistpubs/SpecialPublications/NIST.SP.800-57pt1r5.pdf)

-- Table 2: NIST 800-107r1 Section 4
(https://nvlpubs.nist.gov/nistpubs/Legacy/SP/nistspecialpublication800-107r1.pdf);
 and also note that this security strength is collision resistance

-- Table 3: RFC7748 for Curve25519 and Curve448; NIST curves is ??

-- Table 5: NIST 800-57Part1R5, Section 5.6.1.1
(https://nvlpubs.nist.gov/nistpubs/SpecialPublications/NIST.SP.800-57pt1r5.pdf)

** Section 1.1.  In the spirit of inclusive language s/man in the middle/on
path attacker/

** Section 1.1.
It is suggested that the minimum secure hashing function that should
   be used for key exchange methods is SHA2-256

After the previous sentence just went to the effort of defining the security
strength of the SHA-* algorithms by bits, is there a reason the minimum
strength baseline is framed as an algorithm name rather than a number of bits?

** Section 3.4.  This section notes that some legacy situations would find
group14 useful.  Could you elaborate on that situation?

==[ Editorial
** Editorial.  Be consistent with the naming of algorithms with case and
hyphenation.  For example:

-- Section 1.  s/sha1, sha256, sha384, and sha512/SHA-1, SHA-256, SHA-384, and
SHA-512/ -- Section 1.2.2.  s/sha256/SHA-256/ -- Section 1.2.2.
s/aes128/AES-128/ -- Section 1.2.2. s/aes192/AES-192/

(There are likely more instances than those named above)

** Editorial.  Be consistent on either SHA2-256 or SHA-256

** Section 1.1. Typo. /is is/it is/

** Section 1.2.2. s/Cipher/cipher/

** Section 3.2.1.  Editorial.  s/4K/4000/

** Section 3.4.  Typo. s/key exchanges methods/key exchange methods/