DNS-over-HTTPS

https://developers.google.com/speed/public-dns/docs/dns-over-https

by mikecarlton • 10 years ago

321 148 10 years ago

developers.google.com

tigarcia• 10 years ago

I wonder what the performance hit of something like this would be. It seems like the ssl connection would be a bottle neck for the page load.

JoshTriplett• 10 years ago

Probably not much, especially if you can maintain a persistent HTTP/2 connection to the DNS server.

Panino• 10 years ago

I use DNSCurve, which adds <1ms to latency. That's with X25519 and XSalsa20-Poly1305. Assuming a persistent connection, DNS-over-HTTPS might be similar with AES-NI or ChaCha20-Poly1305. The real speed issue is the number of round trips. DNSCurve is Zero-RTT, and assuming a persistent connection, DNS-over-HTTPS should probably be too at least once it's up and running.

And then consider that lots of pages have megabytes of javascript fetched from multiple sources, big and often unoptimized images, expensive screen redraws, etc.

Modern crypto doesn't affect performance at all. Hell, even PQCrypto-encrypted-DNS with 64KB public keys would be fast compared to the modern web. There's no reason to worry anymore about modern crypto affecting performance. It's just not an issue.

toast0• 10 years ago

If you had the TLS connection open to Google, there's a bit of overhead because the request is longer, and the response is longer than native DNS, plus http headers (hpack and content-encoding would help), but I wouldn't expect it to spill to a second packet for either request or response. Encrypt/Decrypt is probably not a big deal compared to network latency. Assuming Google runs dns.google.com in the same locations it runs its port 53 services, then it's still one round trip either way.

If you don't have the connection open, you still have to do a port 53 DNS lookup to find out where to connect (1 round trip to configured dns server), plus open a tcp connection (1 round trip), setup tls (1 round trip, assuming TLS false start), DNS request (1 round trip); so 4 round trips vs 1.

eridius• 10 years ago

I find it somewhat amusing that in order to use DNS-over-HTTPS you must first resolve a domain using "normal" DNS (dns.google.com). You'd think they'd go ahead and publicly advertise a static IP for that so you can use it without relying on normal DNS.

microcolonel2• 10 years ago

The certificate has to match, so I don't think there would be a problem.

bluejekyll• 10 years ago

Assuming none of your CAs have been compromised.

kazinator2• 10 years ago

But that is a bit harder to spoof. Suppose someone hijacks your plain text DNS to take over "dns.google.com". Their fake site will not have the right SSL keys, so your DNS-over-HTTPS client will reject it.

tony-allan2• 10 years ago

I've been playing with some code running as a resolver on my Mac. I had to seed it with some of the google IP addresses to resolve https://dns.google.com to get it going.

fivesigma• 10 years ago

Agreed, an anycast IP should be provided just like that of their resolvers.

thinkMOAR• 10 years ago

yeah would make sense i guess if they used another ip address in their 8.8.8.8 like range and offer it directly on ip.

api• 10 years ago

Why is this news? Any protocol can (usually trivially) be tunneled over http(s).

nickpsecurity• 10 years ago

I believe the significance is that it's being done, how, and by an Internet giant. There's an impact difference between random person on Github doing DNS over HTTPS and Google deploying it.

jcrites2• 10 years ago

You know, I've had thoughts along similar lines in the email space (SMTP). HTTP is such a fantastic protocol and an amazing amount of engineering effort has gone into it compared to SMTP. I've wondered whether there would be any interest in defining a translation from SMTP into HTTP, with an eye toward eventually deprecating SMTP in the fullness of time.

For example, to send an email, perhaps you just send an HTTP POST request to a canonical endpoint (email.example.com), instead of all the rigamarole that SMTP servers require with a unique text protocol requiring multiple round trips. Have you seen the number of SMTP commands involved in sending a single email? Here's an abbreviated transcript of what it's like to send an email using `telnet`:

  # Wait for banner from server (RT #1)
  220 email-inbound-relay-1234.example.com ESMTP Sendmail 1.0.0; Thu, 29 Sep 2016 19:22:12 GMT
  
  # Send EHLO and wait for reply (RT #2)
  EHLO example.com
  250-email-inbound-relay-1234.example.com Hello ws-1.example.com [1.2.3.4], pleased to meet you
  250-ENHANCEDSTATUSCODES
  250-PIPELINING
  250-EXPN
  ...
  250 HELP

  # At this phase you should really send STARTTLS and negotiate a TLS connection,
  # but we'll just ignore that for now and proceed plaintext.
  
  # Specify sender (RT #3)
  MAIL FROM: jcrites@example.com
  250 2.1.0 jcrites@example.com... Sender ok
  
  # Specify recipient (RT #4)
  RCPT TO: jcrites@example.net
  250 2.1.5 jcrites@example.net... Recipient ok
  
  # Specify message headers and content (RT #5)
  DATA
  354 Enter mail, end with "." on a line by itself
  Subject: Hello, world!
  
  Fun stuff
  .

  # Wait for reply (RT #6) 
  250 2.0.0 u8U1LC1l022963 Message accepted for delivery

Furthermore, if you skip these steps or front-run them, some servers will consider that suspicious or spammy behavior. (RFC 2920 properly allows this as an extension called pipelining, advertised in the EHLO reply above.)

With full use of SMTP extensions, things are a bit better than I imply but still frustratingly suboptimal. For example, I've run across ISPs who purely for their own load management reasons want to close an SMTP session at the TCP level after an arbitrary number of emails have been sent (N < 100)! Why would they desire that? If we're going to exchange more messages, then it's certainly less efficient for us both to negotiate a new TCP session and TLS session, rather than reuse the one we already have, but such is the practice of email. So message sending often can be as inefficient as this. When sending to some ISPs worldwide it's not uncommon for a single message to take seconds to deliver under normal network conditions.

How about we replace all of that with an HTTP POST to email.example.com, specifying the email headers and content with the POST body, and the sender and recipient as headers or querystring parameters? I think it'd be nice to get there eventually rather than drag SMTP on forever. All of the effort that goes into HTTP clients, servers, and security could benefit the email community as well.

Proper TLS security is still nascent in SMTP -- only because of Google's actions with Gmail and their Safer Email [1] initiative has TLS really come into widespread adoption at all. Today, although a lot of email is nominally taking place over TLS, most clients are not involving any sort of path validation and the connections are susceptible to MITM; and email clients don't specify client TLS certificates nor do servers examine them. If we were to employ it, TLS client certificate authentication could be an effective way to prevent email forgery, e.g., require email from example.com to be sent from a client with a TLS certificate for that domain. This kind of thing would be much easier to achieve in the HTTP world than in the SMTP world. We could also take advantage of HTTP/2 pipelining to efficiently deliver a lot of traffic across just one TCP connection.

We'd still need most of the effort invested into email, such as all of the effort fighting abuse, and mail servers would still need to buffer outbound messages and authenticate inbound ones, etc. (and we'd still need SPF, DKIM, DMARC) but at least it would simplify the foundational and protocol-level work, like what's involved in bootstrapping a new email client or server from scratch. You could write basic code to send an email in a few minutes using an HTTP library in any language. SMTP is pretty well entrenched, however, and the incremental benefit is probably not large enough, so I don't have my hopes up.

[1] https://www.google.com/transparencyreport/saferemail/

chatmasta• 10 years ago

Isn't this effectively what any mail API does? Sendgrid, mailgun, Amazon SES, etc. all have HTTP APIs for interacting with email.

jcrites2• 10 years ago

Yes, that's an apt comparison. Proprietary APIs for email exist today between parties that trust each other (clients and their service providers). What I'm proposing is to take it further and devise a standard HTTP-based protocol for message transmission between equal parties like ISPs, and for scenarios where there isn't preexisting trust.

For example, today if you use an HTTP API to submit a message to SendGrid or Mailgun or Amazon SES, that's a trusted relationship based on an account you have with the service, typically a paid relationship. Each provider has its own unique API, which is incompatible with other providers.

In the next step of that process, your service provider's Mail Transfer Agent (MTA) communicates with the final destination mail server (`example.com MX`), and that part is a peer relationship between ISPs (quasi-trusted or untrusted). This communication is all SMTP today, and I'm proposing the idea of a standard way to transmit emails over HTTP in this layer too, in such a way as that it would, in the fullness of time, obsolete SMTP.

kijin2• 10 years ago

FastMail has been working on something called JMAP [1] for quite some time. It's an HTTP-based replacement for IMAP. Perhaps it could be extended to replace SMTP as well. Then we would have a single, HTTP-based API for all of our email needs.

[1] http://jmap.io/

sneak5• 10 years ago

http://www.catb.org/jargon/html/Z/Zawinskis-Law.html

duskwuff• 10 years ago

I'm not convinced that's a useful generalization. Beyond that IMAP and SMTP do something vaguely related to email, there's very little overlap between the two protocols.

rickycook• 10 years ago

you don't need a canonical endpoint per se. just a SRV record

chris_wot5• 10 years ago

Active Directory already uses SMTP for synchronising between sites.

marcosdumay• 10 years ago

I'm recently thinking a lot about email because of project[0], and yes, I do agree that it would be great to tunnel SMTP inside HTTP(S). (But yes, I'd go with a SRV entry, not a constant name.)

But no, it's not a great idea to let HTTP replace SMTP. SMTP is a stateful protocol, and while that brings some problems, it also brings some gains. For example, backend servers can keep connections open between them, peers can negotiate resource usage in real time, and the entire extension model is only possible because of connection state.

You'd lose all of those (or replace them with ugly hacks) by tunneling over stateless HTTP. It's a worth trade-off on some situations (like when you are behind a bad proxy), but not always.

[0] sealgram.com

babangida• 10 years ago

HTTP-over-DNS would also be neat :) I think I would be able to get internet access in some airports if I had HTTP-over-DNS

skissane• 10 years ago

IP-over-DNS has already been done.

https://news.ycombinator.com/item?id=7619259

jsmthrowaway2• 10 years ago

As has IP over ICMP echo requests, which I have actually found useful: http://code.gerade.org/hans/

kijin2• 10 years ago

DNS-over-HTTPS-over-Tor-over-DNS-over-ICMP is where it's at. None of the three-letter agencies can eavesdrop on your DNS queries now! It might even be faster than RFC 1149.

https://www.ietf.org/rfc/rfc1149.txt

chris_wot5• 10 years ago

Not if you actually use RFC 1149. You're operating at layer 1 and 2 when you rely on birds.

I'm waiting for the day when RFC 1149 is expanded to incorporate a layer 2 tunnelling protocol. I suspect this issue is not the initial encapsulation but how to extract the original frame without it getting mangled.

takeda• 10 years ago

It might even be faster than RFC 1149

Depends on definition of fast, the latency indeed could be better, but your bandwidth is only limited by the size of your USB stick, and most often would be much faster than current solutions.

satbyy• 10 years ago

Not just HTTP but you can TCP-over-DNS:

    apt-get install dns2tcp

Pretty easy to use too (though development seems to have stopped)

nathancahill• 10 years ago

Don't those networks hijack DNS to display captive portals? I always like poking around domains on "free limited-browsing" networks trying to get an open connection to the open web.

danellis• 10 years ago

Not all of them. Some of them hijack HTTP, so you resolve your destination address as usual, but when you actually attempt to connect, you're redirected. This seems to be becoming less common, though, unfortunately.

acidtrucks• 10 years ago

This is great, but google doesn't need to eavesdrop on us when they compel us to use their avenues for our every action.

kyrra• 10 years ago

It is optional to use. Just like it's optional to use Googles Dns servers at 8.8.8.8 and 8.8.4.4. The advantage with this is the extra security you get with HTTPS.

Google DNS tends to be one of the fastest DNS servers you can use (just benchmark them against other options). The IPs are anycast, so you will likely be served by the Google data center closest to you.

As for what they log, check it yourself: https://developers.google.com/speed/public-dns/privacy

deathanatos• 10 years ago

So, what DNS server do you use? I trust Google's DNS (I use the normal DNS ones, 8.8.8.8 and 8.8.4.4) a lot more than I trust Comcast's DNS servers. I'm sure there are others out there, of course, but 8.8.8.8 is good, reliable, and easily memorized.

ams6110• 10 years ago

I use OpenDNS

sneak5• 10 years ago

Comcast is the one sending you the (unsigned, unencrypted) response packets from 8.8.8.8.

You might as well use the Comcast ones.

spc476• 10 years ago

I run my own, but then again, I also run my own web and email services. But in my gut, I have the feeling that at some point, Google will become the Internet (or even worse---we have the GoogleNet and FacebookNet and never the twain shall share).

Until then, I'll run my own stuff.

kuschku3• 10 years ago

So, what DNS server do you use?

The chaos computer club runs their own, which happens to answer usually just as fast as Google’s DNS. (And which isn’t subject to censorship, Google’s DNS, like Comcast and most US ISPs, censor several domains of piracy websites, although the domains are still existing in the ICANN database, and are reachable through most other DNS servers)

robertcope• 10 years ago

I use OpenDNS. My home network is setup so that all DNS requests are sent via dnscrypt to OpenDNS. This ensures that Comcast (or whoever) doesn't ever see my DNS traffic and can't muck with it.

seanmcelroy• 10 years ago

DNS-over-QUIC would be a much more compelling technical proposal from Google as a standard

sashametro5• 10 years ago

Note that although it is not documented, when you query the Google DNS-over-HTTPS service from Chrome, it will usually use QUIC. You can check this at chrome://net-internals/#quic, and will probably see something like this (look DNS/HTTPS/QUIC/UDP/IPv6!):

dns.google.com:443 true QUIC_VERSION_34 [2607:f8b0:400d:c03::8a]:443 10544469510527000173 0 None 2 9 0 9 true

An independent implementation of QUIC (are there any outside of browsers?) would probably work much the same, modulo any changes during the ongoing standardization of QUIC.

davidu2• 10 years ago

We did the same thing w/ JSON responses: https://www.openresolve.com/

This is a bad idea outside of experimentation. Not to be used for production.

If you want to secure DNS look at QUIC, TLS, or my favorite, DNSCrypt (which I funded).

prewett• 10 years ago

Why is this a bad idea? You can't just say "it's bad" with no justification.

As a user, I can sure think of some countries with broken Internet access where this would come in handy.

davidu2• 10 years ago

I'll rephrase, it's way better accomplished with UDP without sacrificing security in the ways I list.

Running DNS over HTTPS over TCP isn't needed. It doesn't solve a problem.

Doing JSON DNS for OOB DNS checks is useful since most applications speak HTTP. :-)

stevekemp• 10 years ago

Yup I threw together a toy too:

https://dns-api.org/

For debugging and diagnostics it is useful, for querying via a local resolver not so good.

sashametro5• 10 years ago

dns.google.com:443 true QUIC_VERSION_34 [2607:f8b0:400d:c03::8a]:443 10544469510527000173 0 None 2 9 0 9 true

An independent implementation of QUIC (are there any outside of browsers?) would probably work much the same, modulo any changes during the ongoing standardization of QUIC.

jetsnoc• 10 years ago

I think this could be more useful if there was a local client that installs and proxies. E.g., A traditional query to localhost:53 gets translated to DNS-over-HTTPS.

joshAg2• 10 years ago

Why can't you just send DNS messages over an SSL/TLS socket? What's the value add for http and REST?

LukeShu2• 10 years ago

I would assume being able to reuse the connection for multiple requests. Setting up the TLS connection is quite a bit more expensive than raw TCP, and especially UDP (most DNS happens over UDP). For longer connections, the additional overhead is minor, but for the extremely short DNS messages, I would imagine that a TLS connection per DNS request would be some pretty substantial overhead.

Edit: The page mentions that this allows web applications to make their own DNS requests, possibly looking up things other than A/AAAA records that the browser normally requests.

eggnet• 10 years ago

http and rest are not the only ways to reuse a socket. You could just write the packet to the TLS stream, raw, and keep the socket open.

joshAg2• 10 years ago

that's what ssl tickets are there for.

heck you can even do that over udp with dtls, if you don't want to deal with setting up and tearing down tcp connections.

comex• 10 years ago

Web applications can't initiate raw TLS connections.

peburrows• 10 years ago

That's not true. Sure, many languages require you to drop down to a lower-level API to create a vanilla TCP connection, but if the language you're using doesn't provide a way to open a TCP socket and do the TLS negotiation dance, then you've probably chosen the wrong language.

paulddraper4• 10 years ago

Because HTTP is the new narrow waist of the internet.

hrjet• 10 years ago

Corporate proxies / firewalls.

mseebach• 10 years ago

It's an API that returns a document. Nothing fancy, no bells and whistles. If, for literally anything else, someone had suggested building such a service using raw sockets, they'd rightly be laughed out of the building.

Twilio isn't implemented using AT commands either, and for the same reason.

chris_wot5• 10 years ago

What, resolving using a socket is now considered ridiculous?

nothrabannosir• 10 years ago

The comparison with Twilio is unfair.

DNS latency is an entire round trip added to every single fresh domain lookup you make. That's a lot of times, and we want those to be as fast as possible. At that point, the raw sockets vs full blown HTTP over TLS over TCP debate matters.

Twilio, on the other hand, is used in situations with comparably laughable latency requirements. At least two orders of magnitude.

Not saying it's doa, but the question has merit.

ddalex• 10 years ago

Because Google thinks by default in terms of HTTP and browsers, and can't think that not everything is on Web.

acdha• 10 years ago

Given how successful they've been at that, I'm curious why you seem to view that as an aspersion on them rather than something to learn from? Shouldn't that tell us something about deploying internet-scale services?

(and, to be clear, the answer is yes, namely that a custom protocol has to deliver a lot of value to make up for having to deal with the deployment headaches inherent to anything less supported by firewalls, NAT boxes, etc. than HTTP/HTTPS)

thewisenerd• 10 years ago

(including DNS-based Internet filtering)

What guarantees that they wouldn't start filtering URLs on their own (upon request by DMCA, or FBI)?

I do get that they say what they log ( https://developers.google.com/speed/public-dns/privacy ), yet if in case this ever does become a _commonplace_ thing, they'd be easily able to obtain IP addresses of users trying to access blacklisted websites, and hand them over to officials (upon request, maybe?).

rascul2• 10 years ago

This won't be overly useful (to me) unless/until the system resolver supports this and I can implement this on my own DNS server(s). Seems like a good idea, though.

hrez• 10 years ago

https://github.com/wrouesnel/dns-over-https-proxy

rascul2• 10 years ago

I will still prefer the system resolver to support DNS over HTTPS natively, but this option could work.

therusskiy• 10 years ago

I've actually just written a blogpost about it. http://www.dmitry-ishkov.com/2016/09/dns-over-https.html You can run a local DNS server which is gonna use Google's DNS-over-HTTPS. But as eridius noticed you still have to resolve dns.google.com

garganzol• 10 years ago

How fast does it work? What perceived latency does it have during usual web surfing?

tssva2• 10 years ago

I would not use that implementation. It is broken in multiple ways. The most impactful to normal browsing is that it only supports a couple of RR types which doesn't include CNAMES.

tssva2• 10 years ago

I didn't mention it in my original comment because I thought the code didn't exist anymore but I found an old Time Machine backup disk with the code on it for an updated version of the referenced implementation. I have put it up on Github at https://github.com/tssva/dnshttps-proxy. I need to throw up a README and give attribution. Will get to that later today.

This version will support all RR types supported by the miekg/dns library which is the vast majority of them and any you are likely to come across in the wild. It also allows you to specify regular DNS resolvers which can be used in two ways. As fallback if connectivity to the DNS over HTTPS service fails or to always use to resolve specific domains. It also allows you to restrict access to the proxy to certain networks. The rest of the code should be IPv6 friendly but for some reason I implemented the access list in a manner that only supports specifying IPv4 networks. Guess I have something to work on.

If no DNS resolvers are specified it attempts to use the Google Public DNS servers to resolve dns.google.com. If DNS resolvers are specified they are used to resolve dns.google.com. A flag to always use the Google Public DNS servers would be useful, so now I have 2 things to work on.

As far as performance impact I have generally seen from 20 - 80msec of additional delay. Using a caching resolver behind the proxy would help mitigate this. As is the additional delay is pretty much unnoticeable when web browsing.

sashametro5• 10 years ago

There are several different implementations of proxies for DNS-over-HTTPS:

https://github.com/aarond10/https_dns_proxy (C) https://github.com/pforemski/dingo (Golang) https://github.com/tssva/dnshttps-proxy (Golang) https://github.com/wrouesnel/dns-over-https-proxy (Golang) https://github.com/CodeFalling/dns-proxy-https (Javascript)

I'd heard that somebody was working on DNS-over-HTTPS support for https://github.com/getdnsapi/getdns at the hackathon in Buenos Aires in April just before DNS-OARC / IETF-95, but have seen no evidence of that.

zdw• 10 years ago

DNSCurve solved this years ago: http://dnscurve.org , with implementation notes here: https://dnscurve.io

sneak5• 10 years ago

see also: Internet Mail 2000

AliceWonderMisc• 10 years ago

No it didn't. DNSCurve only solves recursive to authoritative. The request from a typical PC to recursive is still without encryption. And provides no mechanism for the PC to even know whether the result it receives is valid or not or if DNSCurve was even used by the recursive.

amluto• 10 years ago

Why doesn't Google include the entire DNSSEC signature chain in the response? Their current approach to DNSSEC validation seems quite weak. Sure, I can query them and get an answer with AD set, but then I need to trust that they didn't tamper with the response.

drizzentic• 10 years ago

Why do I need dns over http?

dtjohnnymonkey• 10 years ago

What's the purpose of explicitly specifying the "random_padding" parameter? Couldn't the client send any arbitrary unused query argument as padding?

pshc• 10 years ago

I can think of two non-technical reasons: as an explicit reminder to devs about side-channel attacks, and also to guarantee the key "random_padding" will never be used for anything else.

KaiserPro2• 10 years ago

nice toy, but there are some things to be considered:

1) "secure DNS" is a solved problem 2) DNS is simple 3) responses normally easily fit inside one packet 4) DNS is fast

HTTPS is a slow, wordy and inefficient protocol. Forcing everything into JSON just compounds the problem.

strictfp• 10 years ago

"nice toy". Very succinct diss.

viraptor2• 10 years ago

1) "secure DNS" is a solved problem

No, not in practice. You can easily MitM DNS and nobody is verifying DNSSEC by default. On the current internet, secure DNS just doesn't exist.

KaiserPro2• 10 years ago

the mechanism is there, people are not choosing to use it.

That is because security is hard.

This doesn't mitigate MitM attacks, as upstream DNS records can still be spoofed

WE go from a fast, decentralised, resilient and low overhead system, to a centralised chatty and fragile behemoth.

It still doesn't give end to end encryption, its just a slow encrypted proxy.

sashametro5• 10 years ago

Google Public DNS (8.8.8.8) verifies DNSSEC by default. So does Verisign Public DNS (64.6.64.6).

Some measurements of DNSSEC validation show that as much as 15% of Internet domain lookups validate DNSSEC: http://stats.labs.apnic.net/dnssec/XA. Approximately half of that is due to Google Public DNS validation (many sites use both Google Public DNS and other resolvers that do not validate, so do not actually validate DNSSEC overall).

It is very true that less than 1% of DNS zones are signed with DNSSEC, so it is true that "secure DNS" doesn't practically exist, but this a serving side issue, not a lack of client validation.

byuu3• 10 years ago

Currently, web-based applications must use browser extensions to take advantage of advanced DNS features such as DANE, DNS-SD service discovery, or even to look up anything other than IP addresses. Extensions for features that depend on DNSSEC must validate it themselves, as the browser and the OS may not (be able to) validate DNSSEC.

If only there were some way for Google to let people take advantage of advanced DNS features without requiring browser extensions ... alas, they'd probably need to add that code to a web browser. But then, where would they find a web browser they could add such code to? Ah well. Google should ask those web browser vendors why they won't implement DNSSEC, at least. Maybe start with asking the browser with the highest market share, whichever that one is.

hannob2• 10 years ago

agl has explained in detail why they don't do that: https://www.imperialviolet.org/2015/01/17/notdane.html

tl;dr they can't, because DANE is undeployable in the current Internet.

byuu3• 10 years ago

Thank you for the link. I was previously only working from these links:

https://www.ietf.org/mail-archive/web/dane/current/msg06996....

https://bugzilla.mozilla.org/show_bug.cgi?id=1077323

https://bugs.chromium.org/p/chromium/issues/detail?id=50874

Instead, for this we have HPKP, which is a memory-based pinning solution using HTTP headers.

The problem with HPKP is that you still need a certificate from a CA. And if you want wildcards or a >90 day length (regardless of what you think of their security, many people do -- the biggest sites on the internet have both), that means paying money. And it also still leaves you vulnerable to MitM rogue CA attacks.

HPKP requires the user to connect the first time to get the pinned key. If an MitM has a fake certificate for your domain, they can send that to you on your first connection and fool you. DANE does not have this problem.

Well, to be fair, DANE has it for the DNSSEC provider used. But that is one thing to trust, and said certificate can be bundled with the OS or browser. One thing to trust beats the current 2000+ intermediate CAs we have to trust.

Further, DANE allows a way to verify self-signed certificates, allowing security to be free for everyone. We could see a lot more innovation than just certbot if Let's Encrypt weren't the only way to generate free certificates. For just one example, web servers could generate certificates from fresh installs; zero configuration requied. Like Caddy, but in nginx and Apache.

Lastly, HPKP is riskier. You have to include a backup pin. But, what would happen if your had your own pinned, and StartSSL as the secondary? And you set HPKP for a year? And two weeks from now, Mozilla revokes StartCom entirely? Well, good luck with that one. Deleting HPKP is a royal pain for a regular user (about:permissions in Firefox, chrome://net-internals#hsts in Chrome)

We also have pre-loaded pinning in Chrome for larger or more obvious targets.

Nice for Google and Facebook, not so nice for byuu.org =(

It's also worth noting that CryptoCat has committed pinning-suicide in Chrome at at the moment due to their CA having switched intermediates between renewals.

Another good negative of HPKP.

But support for that was removed because it was a bunch of parsing code outside of the sandbox, wasn't really being used and it conflicted with two long-term plans for the health of the HTTPS ecosystem: eliminating 1024-bit RSA and Certificate Transparency. The conflicts are probably the most important reasons for not wanting to renew the experiment.

RSA-1024 is bad, yes. Perhaps we should start asking how we can get DNSSEC on RSA-2048+. Having a commitment to implement it in Chrome, Firefox, Edge, Safari if we do would go a long way toward making that happen, I'm sure. Further, we can reject any RSA-1024 signed DNSSEC after that point, just like we reject weak crypto in browsers today.

If they can't change DNSSEC to stronger crypto, how about they make an alternative? If Google introduces one that has stronger crypto, supports it in Chrome, and offers a free "DNSSEC+" hosting service, I'll definitely take immediate advantage of that.

But the latter is the whole point of DANE -- self-signing. Certificate Transparency is a crutch due to the CA system having 2000+ intermediate CAs that can sign any domain name they want. With DANE, you don't need that anymore. DANE is about providing an alternative to the CA signing business.

And there's nothing stopping users from serving up trusted CA-signed endpoint certificate signatures over DANE/TLSA records. That would obviously remain the only sensible way to do EV certificates. The way I see it, a DANE certificate would act like HTTP does now: you get the globe (or even the question mark circle), but your page actually loads over HTTPS, instead of sending you to Defcon-1 advisories that are all but impossible for the casual user to work around (and indeed, we don't want to train them to work around these warnings anyway.) There's no way this would be worse than plain-text HTTP.

You literally can't avoid it because the root zone transits through a 1024-bit key.

Does this really matter for the root? There are root CAs with RSA-1024 still.

...

At any rate, Google apparently feels DNSSEC+DANE is good enough for this web service API. So, honest question, why offer that if it's really such an unworkable system?

teddyh2• 10 years ago

That argument seems to boil down to “We can’t use any new record types in the DNS ever again because 4-5% of users had problems when we silently tested it”. First, this is defeatism writ large – if we can’t develop anything new, ever, we may all just as well go home and give up. Secondly, these things don’t exist in a vacuum; if a website failed because a user couldn’t access DANE or whatever, this would create pressure on all affected parties to fix the situation. This is how things progress instead of stagnates.

AndyMcConachie• 10 years ago

The root zone ZSK is increasing to 2048 bits as we speak. http://www.circleid.com/posts/20160928_increasing_strength_o...

The article also mentions the number of TLDs that now use 2048 RSA keys is around 1,300.

TrueDuality2• 10 years ago

DANE is not DNSSEC. This API doesn't solve the problem the DANE is trying to tackle (adding additional trust vectors to certificates).

It actually seems kind of lazy. Their argument is that it is to difficult for client software to embed a DNS resolver into the browser so it can check whether DNSSEC was attempted and whether it was successful. The actual validation would still happen at the clients local resolver.

Their solution is to make client software implement a REST API for doing its lookups instead, and the validation is still happening at your resolver (the REST API).

The only thing I see as a positive with this is your DNS requests will be encrypted. The trade off is the complexity of the process of getting your responses and that you'll be subject to the potential of third party censorship, logging of all destinations which will be difficult to opt out of.

jbb555• 10 years ago

The "web" is becoming hack upon hack upon hack.

Beltiras• 10 years ago

Becoming? When has it not been?

SFJulie• 10 years ago

Great idea! Even more leverage for a DDoS attack!

It is a quicksand this idea, it seems fine until you rely on it and are shaken by attacks that just make your service unavailable with very few computers and traffic. And then you are screwed because we still hardly know howto prevent DDoS except by having a huge bandwidth compared to the attackers. Unless you are a megacorp with huge datacenters everywhere it is a bad idea.

But well Google will never become a monopolistic company that behave assholishly, right? They would never push standards that favors them other the few remaining hosting companies on the internet. Wouldn't they?

Dylan168072• 10 years ago

Even more leverage for a DDoS attack!

HTTPS already exists and is slightly less vulnerable than normal DNS traffic.

This opens no new DDoS opportunities. The rest of your post is irrelevant.

chris_wot5• 10 years ago

So to resolve a domain to an IP address without using regular DNS they have opted to use HTTPS which really requires a certificate to be signed against a domain via DNS.

dorianm• 10 years ago

Pretty cool, DNS as an API:

- JSON: https://dns.google.com/resolve?name=doma.io

- Web interface: https://dns.google.com/query?name=doma.io&type=A&dnssec=true

tony-allan2• 10 years ago

httpresolver.py implements DNS over HTTPS in a fork of Paul Chakravarti's dnslib. I have it running as a resolver for my Mac using the command:

sudo python3 httpresolver.py

Have a play with https://bitbucket.org/tony_allan/dnslib

mtyaka• 10 years ago

I find it amusing that they chose apple.com for the example.

youdontknowtho2• 10 years ago

That's fantastic. Wondering why this hasn't happened before?

ingenter• 10 years ago

- It has happened, see the comment below (openresolve).

- It doesn't solve the problem, unlike other existing solutions for encrypting DNS.

- It adds unnecessarily high overhead.

youdontknowtho2• 10 years ago

Awesome.

There maybe more than one problem.

That's relative to the aforementioned problem.

Cheers.

majewsky• 10 years ago

Is there a matrix of X-over-Y implementations? I would assume that we are converging to a fully filled matrix.

OJFord• 10 years ago

If not filled, probably full-rank such that all X-over-Y is possible, via-S-via-T!

pjf3• 10 years ago

Shameless plug (again): https://github.com/pforemski/dingo

poorman• 10 years ago

Why have you disabled "Issues" on your repo?

pjf3• 10 years ago

For now I prefer to communicate through email

garaetjjte• 10 years ago

Why not DNS over TLS? https://tools.ietf.org/html/rfc7858

aomix• 10 years ago

DNS doesn't seem very well secured against determined attackers. But at the same time I almost never hear about attacks done via DNS spoofing. So I guess it harder to attack than I think.

znpy• 10 years ago

Sometimes I think we should all take the Apple approach to this kind of things and deprecate old stuff and/or make new stuff mandatory.

We could just force DNS extensions to be implemented in most/all client/server implementations.

DNS over HTTPS might be okay and work well, but imho is a (smart?) workaround, not a fix.

Why can't we all set a time window (7.5 years? 10 years? 15 years?) to plan massive RFC/protocols updates with possibly-breaking changes?

Edit:fix grammar (not native speaker of English)

DNS-over-HTTPS

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