Re: [Ntp] RFC 5297 Questions

[Daniel Franke <[e-mail]>]

1. There isn't one. None of the contributors had any claims to disclose.

2. This question doesn't entirely make sense because FIPS-140 governs
cryptographic modules, not algorithms. SP 800-140C is what approves
algorithms. So I think what you mean to ask is whether you could use a
FIPS-compliant cryptographic module, which uses only algorithms listed
in SP 800-140C as approved security functions, to implement the
cryptographic functions required by NTS. In that case, the answer is
yes. First of all, the only place in which RFC 8915 specifies any
particular algorithm is where it makes AEAD_AES_SIV_CMAC_256 mandatory
to implement as an AEAD algorithm. It permits negotiation of any other
algorithm registered in
https://www.iana.org/assignments/aead-parameters/aead-parameters.xhtml
as long as the client and server both support it. Some of the
algorithms listed there, such as AEAD_AES_256_GCM, are directly
approved by SP 800-140C. And AEAD_AES_SIV_CMAC_256 is actually just a
composition of AES-CMAC and AES-CTR, both of which are individually
approved, so you could use a FIPS cryptographic module to implement
it. I do strongly recommend sticking with SIV, because otherwise
you'll either need to use non-random nonces (which requires keeping
state), or risk random nonce collisions if somebody floods your server
with replayed packets.

On Tue, Oct 24, 2023 at 8:24 PM Daniel Havey
<dahavey=[e-mail]> wrote:
>
> I have 2 questions about NTS for NTP:
>
> Where may I find the IP disclosure?
> Are any of the crypto algorithms listed FIPS compliant?
>
> If the answer is no then, why not?
>
>
>
> Thanks for your help,
>
> …Daniel
>
> _______________________________________________
> ntp mailing list
> [e-mail]
> https://www.ietf.org/mailman/listinfo/ntp