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Comment by tptacek | Hacker News Reader

Signal Protocol is one of the best documented cryptographic message protocols on the planet, and is accompanied by multiple GPL'd implementations.

https://signal.org/docs/

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which sounds like it could be used to develop a federated protocol. I've heard there is an effort to do an RFC on the subject, but I'm not sure it uses the Signal protocols (for some reason), also there are two of them (I'm confused):

* https://tools.ietf.org/html/draft-barnes-mls-protocol-00

* https://tools.ietf.org/html/draft-omara-mls-architecture-01

Using OMEMO on XMPP is a federated implementation of the Signal protocol. I believe Matrix' e2e encryption is also based on it.

I’m really hoping OMEMO makes it into Openfire (XMPP Server) and Adium (XMPP Client) sooner rather than later, we current use OTR but OMEMO is objectively superior in every way I can see.

In general, servers should have nothing to do with end-to-end encryption, except for not actively breaking it.

OMEMO in particular uses:

- Personal Eventing Protocol (PEP, XEP-0163) to transport key material; and

- core RFC3920/RFC6120 XMPP protocol to transport encrypted messages.

Both of which are already supported by Openfire [see JM-1122]. So, as far as I can tell, Openfire is fully capable of delivering OMEMO messages right now.

https://issues.igniterealtime.org/browse/JM-1122

[EDIT] For Adium OMEMO support, have a look at Lurch: https://github.com/shtrom/Lurch4Adium

I don't think Adium is doing much in terms of active development sadly.

Do you consider SMS a federated protocol?

https://silence.im/

SMS is federated, users of one providers can send messages to users of a different provider. Same with phone calls. Becoming a telephony provider probably takes a bit more investment than with some random Internet based service.

Unfortunately, it looks like the signal people are possibly not friendly to third-party devs and have levied seemingly spurious IP threats against third-party implementations: https://medium.com/@wireapp/axolotl-and-proteus-788519b186a7

Obviously this is just one side of the story, but it sounds rather alarming.

I believed this was debunked by moxie somewhere on HN

Would you mind linking it? I've tried to see his past comments but couldn't find anything dated after the blog post on a first look. Just a lot of LibreSignal stuff.

https://news.ycombinator.com/item?id=11727870

Extract from that comment:

> We haven't patented any of the concepts here, and we've done a lot to explain and popularize them. We're happy for people to use these concepts to build their own implementations of similar protocols, but we don't want people slapping things together and calling that Signal Protocol.

That doesn't debunk anything in the blog post - it reinforces the point that moxie doesn't want any third-party implementations of the protocol.

It sounds like they'll defend the Signal trademark, but not the implementation concepts. I don't see how that's bad.

Especially with crypto, one small implementation error could ruin any security value. It's completely reasonable that they don't want their trademark used with code they aren't responsible for.

Yeah. "You can do whatever you want with our GPL'd code, so long as you follow the license, and we don't have any patents, just don't use our name/branding on stuff we don't control" is a reasonable way to ensure the reputation of your name. It's the same thing Firefox does with Linux distros who want to add their own patches.

> It's the same thing Firefox does with Linux distros who want to add their own patches.

"did", I think. I don't know which distros still run into this, but Debian now ships Firefox (RIP Iceweasel).

Or, conversely, modifications could add to the security value.

Did you read the license?

It’s just one side of the story, but after Moxies comments regarding LibreSignal, third-party clients, etc, it’s hard not to believe it.

And Moxie disallows people from building third-party clients for the server where 99% of Signal users are on, and without that, group chats aren’t useful.

Since when? You by default use the main servers when you install Noise or signal-cli, despite how Moxie may dislike this fracturing of the Signal client ecosystem.

Moxie still disallows their use of his servers, they just disregard his demands.

And yet even the best of the best cryptographic protocols provide little to no value on very insecure systems like iphone and android.

It's like bike shedding of security, where Moxi focuses on the things he can do but for the systems where it doesn't matter.

I find it odd that someone would say an iPhone is “very insecure” after the USG, of all players, very publicly couldn’t get into a model from right before the security design hardened, not to mention the also very public panic in the IC about losing access to intelligence due to mobile phone developments. That’s a strange position to tout with the underlying implication that PC platforms are better.

Are you broadening “insecure” to mean “centralized, opinionated security architecture designed for tech-illiterate masses that I don’t like?” Because that isn’t what it means.

Very secure means high-assurance for both hardware and software, very insecure means no assurance for neither hardware, nor software, with control over system belonging to multiple third parties and what not, basically consumer stuff. And threat model for this consumer stuff just doesn't include an adversary capable of intercepting all of your communication and cracking less secure protocols, this is just silly. Because with such level of capabilities an adversary can just target a whole bunch of third parties that have control over your system, penetrate one of them and push a fake update to your system with screen grabbing malware or whatever. By the way, this is an example of a real world attack.

I thought that ended with the government getting into the phone using an exploit, just without forcing Apple's cooperation.

Hence the hardened part. That exploit doesn’t work against any later model, and they spent a lot of money to get into that particular phone. Even with that observation, how can one claim “very insecure?” Do you think it’s that difficult to compromise a PC with physical access? What does secure even mean to people any more?

I trust my phone a hell of a lot more than any general purpose computing platform, and I’d say the same if I owned any number of a significant collection of Android devices. This isn’t phone vs. phone advocacy, just annoyance at opinions that people disingenuously consider factual, useful observations on security.

Only after they paid an Israeli security company for a 0-day vulnerability, which allegedly cost north of $1m.

Interested to know how that amount compares to other OSes, I really don't know what the going rate is on Windows/Linux.

And this was a vulnerability that concerned an iPhone 5c, which did not have a secure enclave. The iPhone 5s was the first model with Touch ID and an secure enclave.

https://www.extremetech.com/mobile/226164-fbis-iphone-hack-l...

I would question how much of this was not being able to get into it and how much was a platform for "we need backdoors into everything".

Ever ask yourself why they did this "very publicly"?

To convince congress to legislate a backdoor.

There are very logical and reasonable reasons for them to advocate publicly. Not everything is a conspiracy.

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