* Jason Livingood:

> If anyone is interested and has time before IETF 75, I¹m happy to take
> feedback before then obviously.

Few players perform NXDOMAIN rewriting.  Instead, ANCOUNT=0 rewriting
is used.  This causes all kinds of problems, including redirections
for example.com when it hasn't got an A record (where some browser
would just fall back to www.example.com), and bad interactions with
IPv6 deployment (because all IPv6-only hosts suddenly have got an A
record).

The malicious site protection does not work reliably because it can be
easily bypassed by the attacker, using IP addresses.

Section 5.3 is pretty explicit in that government-mandated filtering
decisions should be made by executive organs, and not the judiciary.
The IETF should not try to regulate this and should certainly show
more respect for separation of powers.  It should mention that
DNS-based filtering is not acceptable to many governments because it
can be bypassed easily, and it is not possible to block content on
popular sites where the collateral damage of a domain-wide block would
be problematic.

Section 7.1 should be more strongly worded.  Rewriting stuff like
search.msn.com (and reverse-proxying the HTTP traffic) must not be
condoned by a RFC.  Such things are just evil.

No redirection on SERVFAIL seems to be a strange recommendation.
Wouldn't this be a very good reason to provide a diagnostics page,
especially if there's been a DNSSEC validation failure?

As it stands, the product list in Section 8.3 serves no particular
purpose.  Some analysis which browser-based mechanisms are broken by
DNS redirection might be helpful, but this could be done in a
product-independet manner.

Section 8.4 should mention that some (most?) rewriters do not rewrite
subtrees which involve a delegation from the TLD level.  This
addresses a huge range of technical issues.

DNSSEC interoperability doesn't work the way you expect because once
the resolver is security-aware, it will set the DO bit queries, and
you cant tell the non-validating resolvers from the validating ones.
It's also not an all-or-nothing thing because validation depends on
availability of trust anchors.  So you'd have to spoof your answer
according what's permitted by the signed data (particularly the
NSEC(3) records; you don't have to validate the signatures yourself).

The draft must mention DNSBL interactions (and, more generally, the
impact on applications which use DNS as a transport for RPC).  It
should describe approaches how to mitigate issues identified (such as
the IPv6 problem), and show the impact in terms of increased query
count.

There's also a policy impact for ICANN.  Restricted TLDs such as .tel
are not feasible if DNS rewriting essentially removes restriction on
TLD contents.  This also applies to e164.arpa subtrees, where some
national regulators have requested that their subtrees can only be
used for ENUM (and not arbitrary DNS information).

While I'm mostly with Stephane regarding the merits of DNS rewriting,
I think the IETF could still publish a draft on this topic.  However,
it should present pretty stringent requirements which ensure that
rewriting does not adversely impact operations.  The current draft is
closer to a fig leaf, I'm afraid.
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