Say (an encrypted) hello to a more private internet.
Say (an encrypted) hello to a more private internet.
blog.mozilla.org
Say (an encrypted) hello to a more private internet. | The Mozilla Blog
64 comments
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Does this mean your isp can't see the sites you visit anymore?
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Sort of. They can still see which IP address you're connecting to, which by itself or in combination with some minor traffic analysis is quite often enough to identify which website you've visited. Perhaps it isn't if the website puts absolutely everything through a giant CDN like Cloudflare, but in that case it's Cloudflare which gets to see all the sites you visit which isn't a whole lot better than the status quo.
Still, it's a little less information given away at least some of the time. Better to do it than not do it.
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in that case it’s Cloudflare which gets to see all the sites you visit
That's the status quo. CF holds the private keys to all reverse proxy'd sites hosted on it.
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Yes. Use a VPN. I recommend https://mullvad.net/en
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Well, for half of the internet they are going to see AWS ELBs addresses.
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That's how I understood it. With regular https your doing on those websites is already encrypted, but your ISP or whoever sits in between can still se which sites you're visiting. As far as I understand this standard would encrypt this step too.
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Cool. Nice work Mozilla.
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When is this coming to ff mobile?
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Usually with these kind of engine-features, the rollout is simultaneous on desktop and Android.
And it says it's rolling out with version 118 here: https://support.mozilla.org/en-US/kb/understand-encrypted-client-hello
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Does anyone know how to enable this for nginx?
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It's been a couple years since I was involved with ECH, but the implementations at the time were:
The one by the draft's authors in golang (Cloudflare). This is the actual test server. It uses Cloudflare's fork of golang with an enhanced crypto library. https://gist.github.com/cjpatton/da8814704b8daa48cb6c16eafdb8e402
BoringSSL used for chrome. There are nginx builds with BoringSSL, but I don't know if the setting are exposed.
https://boringssl.googlesource.com/boringssl/+/refs/heads/master/ssl/encrypted_client_hello.cc
WolfSSL which I never got around to playing with.
https://www.wolfssl.com/encrypted-client-hello-ech-now-supported-wolfssl/
NSS which is Mozilla's TLS library. There is a test server buried in there some place for unit testing.
https://firefox-source-docs.mozilla.org/security/nss/index.html
With that, you ALSO need a DNS server that supports DNS over HTTP (DoH) and HTTPS service binding records (https://datatracker.ietf.org/doc/draft-ietf-dnsop-svcb-https/).
Bind9 had branches for both and I was able merge the two to satisfy that requirement.
When connecting to such a server, you MUST NOT use a DNS resolver hosted by any origination along the path from client to server as they can correlate the host from the DNS request with your encrypted client hello. You can actually man-in-the-middle ECH to decrypt the client hello by overriding the hosts record when controlling the DNS resolver. My project was testing this for parental controls.
Keep in mind, ECH really only benefits users connecting to a CDN. That is, when multiple services are behind the same IP. It masks which host the user is going to for any hop between the client and server.
Any data mining company worth their evils will have an IP to DNS index to figure out the host when only one is behind an IP.
This marginally gives some privacy to users. It hides the host from your ISP. It REALLY benefits browser companies and CDN hosts. What hosts a user is visiting now becomes exclusive data for those companies thereby driving up the value of the data. Assuming you aren't being stupid with your addons.
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Users using DNS-based filtering may need to tweak their configuration in order to make use of ECH. Firefox needs to be configured with a DNS-over-HTTPS server in order to make use of ECH. Depending on whether the DNS filter is locally hosted or hosted by an online provider, instructions for connecting to it over DoH will differ and users of these services will need to check their accompanying documentation.
Sooo, I'm a bit lost here. How do I ensure everything's working when I'm using a pihole? I don't think I'm understanding everything correctly
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I think it requires you shut your pihole. Um. sorry. Ill let myself out.
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It sounds like you'll have to set your Pihole as the DNS server in Firefox's settings, and then maybe from there it'll work itself out? Or maybe the Pihole documentation will be updated in the next few days with some instructions on enabling this. I'm unsure myself to be honest.
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That would make sense, wouldn't it? I think I'm going to wait for the pihole team to inform about this.
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So with this the ISP, or someone else sitting in the middle, would not even know the URL you're accessing?
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I don't think so, that'd be straight up impossible unless you're behind a VPN. Your ISP can see every connection made between you and any other server, but a VPN uses encrypted payloads between their servers and you, and they make the requests using their servers, and pass the results to you. That way, your ISP only sees that you're using a VPN, but can't see anything else.
As far as I understand it, ECH uses DoH (DNS Over HTTPS) to encrypt the domain name of your connections, but a direct IP address is always required, and most of the times, it's enough to determine the website, as the ISPs can locate just about anything easily. However, the ISP won't be able to (easily) know anything else about the connection, which remains unbroken between you and the server you're connecting with.
But still a very good feature nonetheless.
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In my opinion, Firefox should give an option to enable ECH forcefully for users like me who has AdGuardHome/Pi-Hole running on Home Network. Currently, if DOH is disabled in Firefox setting, ECH won't work, as per Firefox. 😦
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How about you first standardize it?
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It's being worked on. https://datatracker.ietf.org/doc/html/draft-ietf-tls-esni
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64 comments
All well and good, but sadly this relies on the hosts managing DNS to include specific entries in their DNS configuration for keys to use during the encryption process. Unfortunately the vast majority of hosts probably won't be bothered to do this, similar to DNSSEC.
And HTTPS relies on hosts managing SSL certificates. Web services don't use them until it hits a critical mass, then it becomes weird and broken when you aren't using it.
This just needs some time to settle in.
I remember when absolutely no one used https and then in a matter of a couple years things got really fast. Now you can easily browse with https required and only occasionally find the odd website that doesn't use it (mostly some internet relic). That was such a great transition when it happened though.
Even with tools like Let’s Encrypt, people are still not
implantingimplementing HTTPS?You're right, but HTTPS implementation added real, tangible benefits that everyone could understand. I think ECH is a little more abstract for the average user, which is why I compared it to DNSSEC which has notoriously poor buy-in.
Obviously I hope ECH becomes a well-implemented standard. I'm just rather cynical that it'll be the case.
Apparently, Cloudflare already supports ECH, and a not-insignificant number of websites use them.
Unfortunately though, is that it's cloudflare
Wouldn't it be better if reverse proxies simply had a "default key" meant to encrypt the SNI after an unencrypted "hello" is received?
Including DNS in this seems weird.
What would stop a MITM attacker from replacing the key? The server can't sign the key if it doesn't know which domain the client is trusting.