Watson Ladd wrote:
> On Sat, Feb 15, 2014 at 10:08 AM, Paul Vixie <[email protected]> wrote:
>> ... The answer is that Curve25519 passes all
>> requirements on elliptic curves: it is safe against all known attacks.

SSH1 was safe against all known attacks, until the first one. turns out
"integer underflow" was not previously a known attack. let's all learn
some caution about what we define as "safety", lest the gods strike us
down for our temerity.

>>> Thirdly, this proposal ignores entirely how to validate the server
>>> over the TLS connection. Does it need a certificate? Who should be
>>> allowed to sign it? How should it be validated? DNSSEC provides a PKI,
>>> and this proposal provides another one. Their interactions will not be
>>> fun.
>> see above; i don't think this proposal offers or intends to offer a PKI,
>> merely a hop-by-hop confidentiality option. DNSSEC will still be required.
>
> If we don't have authentication, we don't have confidentiality: MITM
> is possible.

the MiTM problem is due to X.509 not TLS per se. DANE stops MiTM for
TLS. my comfort level with DTLS, or STARTTLS-over-EDNS, or TLS or SSL,
is the same: low with X.509 since most nation-state actors and many
criminal actors can feed any endpoint a certificate they will believe no
matter what the name is; high once we pitch X.509 into the ash bin of
history and get DANE running everywhere.

> Secondly, "hop-by-hop" means what for DNS? If all this secures is the
> connection between a client and the full resolver, then this doesn't
> protect the confidentiality of anyone doing a DNSSEC query, as
> resolvers cannot return the data required to validate DNSSEC.

all arguments of the form "DANE can't be deployed because of
middleboxes" beg the answer "we will have to send JSON over HTTPS using
a RESTful query to protect the last mile , see bortzmeyer's draft on
that subject."

> It also
> doesn't protect against the cache recording what is being looked up.

well, yes. if someone wants to look stuff up in DNS without middleboxes
knowing what they looked up, they have to use a VPN.

>> dnscurve was offered to the ietf community but it didn't stick for
>> reasons unrelated to this newer proposal. i don't see any sense in
>> comparing their installed bases.
>
> That reason was caches everywhere are very useful to reduce load on
> DNS servers,

well, no. caches everywhere are very useful to reduce latency for
clients. authority servers today must be so massively overprovisioned
for DDoS reasons that any multiple of normal load even if no caches
existed anywhere would be pretty much line noise.


vixie
_______________________________________________
perpass mailing list
[email protected]
https://www.ietf.org/mailman/listinfo/perpass

Reply via email to