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Disappearing messages for Signal

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Re: Disappearing messages for Signal

#151

Post by kelnos »

rorosaurus wrote: post #73
oconnore wrote: post #9

Earlier quoted context omitted.

If their sense is that -- after configuring 1 week self destruct, the people they're talking to likely won't be keeping months and months of chat logs on their phone anymore -- it's a very true sense of security.

At least until the Jailbreak tweak is released with patches out this feature, allowing people to retain everything they want. I don't disagree that it works for the average user, but I do agree with the sentiment that it is a false sense of security. Unless maybe you cryptographically verify the deletion (is that possible?) and notify the other party of the successful deletion. But even then a copy could be made befo…

There's no need to jailbreak anything. The code for the client is open source; you merely have to remove the code that obeys the remote request to delete, and rebuild and reinstall.

Re: Disappearing messages for Signal

#152

Post by abysmallyideal »

lqdc13 wrote: post #39

I love Signal and this seems to be a stab at Wickr since from what I've heard that is the reason people prefer it to Signal sometimes. Having said that, it has a couple of problems: 1. Images are downsampled without warning. There should be some sort of warning or mini info box for the times when the images are downsampled and there should be information about the changes in resolution. 2. If one uses it as the main…

Doesn't downsampling have the affect of preventing the use of more popular stego apps? Makes me wonder if there's something hidden in 25519. According to recent publications, it's easy to create backdoored primes fashioned to simplify search methods. Although those were for SNFS and DH, there are likely applications for searching the ECDH space.

Re: Disappearing messages for Signal

#153

Post by uph »

miguelrochefort wrote: post #141

Who exactly uses Signal? Why do you think it's secure?

Edward Snowden, Bruce Schneier, Matt Green and a few more. I think it's secure because it's been audited, because I trust the experts who say that it is secure, because of http://support.whispersystems.org/hc/en-us/articles/21247776... and because of https://whispersystems.org/bigbrother/

Re: Disappearing messages for Signal

#154

Post by tdkl »

darklajid wrote: post #138
tdkl wrote: post #126

Earlier quoted context omitted.

That's completely optional and not the default. It does what it says, makes known users easier to find,but you can still search for them without that.

This is either new or wrong. I just posted a sibling comment to the GP: At least in August it wasn't optional and happened automatically on Android, unless you were running M: The permissions requested during installation (contact access, to even have a way to offer this feature) of the app were exercised without asking for further consent and your contacts were shared with their server unconditionally.

There'a a on/off switch to share contacts under Wire Settings/Options and it's off by default at installation, (it was at the end of August when I started using the service).

Don't know though if the app asked for permission to access contacts like it should, since I don't have any device with M.

This is from the Privacy whitepaper how they manage the data shared [1] :

> Address books are uploaded to backend servers if users grant client applications access to their contacts. Each address book entry is first normalized, i.e. phone numbers are ensured to be in E.164 form. Entries are then hashed (using SHA- 256) and base-64 encoded before being transmitted to the server. No other information, such as names, addresses, birthdates, notes, etc. are extracted from the address books. Address books are checked for changes every 24h by clients and changes are uploaded again. Uploaded address books are used to match users on Wire, i.e. to suggest new contacts and to automatically create connections between users (see section 2.2). The matching algorithm creates connections between users who have each others e-mail address or phone number in their address book.

[1] https://wire.com/privacy/

Re: Disappearing messages for Signal

#155

Post by uph »

kuschku wrote: post #147
moxie wrote: post #74

Earlier quoted context omitted.

> Moxie has threatened to shut LibreSignal down if they allow LibreSignal users to message normal Signal users, and refused to even discuss alternative solutions. Please cite this. To my knowledge I never threatened anything, and your comment is a response to a quote from the discussion about LibreSignal, where I suggest that they submit a PR with the functionality they desire to Signal. Is that not an alternative? >…

> Please cite this. I’m sorry, what was this entire discussion then supposed to mean? https://github.com/LibreSignal/LibreSignal/issues/37#issueco... If they can’t fork it while still using your servers, and you refuse to allow federation, how the FUCK is it open in any way? How are users supposed to be able to verify the software running on their own systems when you only allow binaries compiled by yourself to commu…

> If they can’t fork it while still using your servers, and you refuse to allow federation, how the FUCK is it open in any way?

What makes you think you have a right to demand federation? Run your own server if you don't like how they're doing it. You have access to the source under a Free Software license https://github.com/WhisperSystems but of course you don't want to actually do any work, you want to complain about what other people do because they don't do it in the exact way you want it done for free.

> How are users supposed to be able to verify the software running on their own systems when you only allow binaries compiled by yourself to communicate with your users, abusing the lock-in effect?

https://whispersystems.org/blog/reproducible-android/

> You only distribute through the Play Store, which doesn’t fully work with microG at the moment, requiring users to install spyware on their devices.

https://news.ycombinator.com/item?id=12689352

Re: Disappearing messages for Signal

#156

Post by pfg »

wtbob wrote: post #111
lenish wrote: post #90

Earlier quoted context omitted.

If we're talking about the actual hash signal uses for this value, then sure, but talking about the number of digits displayed isn't even the right thing to care about, since they're using SHA1 for the hash AFAICT: https://github.com/WhisperSystems/Signal-Android/blob/3.0.0/...

SHA1? SHA1 SHA1 ‽ I'd always thought that OWS had incredibly good crypto — why are they using SHA1? If it's to support relatively short hashes … I just can't even. There's simply no excuse to choose to use SHA1 in 2016. It's not completely broken, it's probably good enough, but why not just truncate SHA2?

SHA-1 is fine in this context. SHA-1 isn't as collision-resistant as it was once thought to be, but that's not a property that you care about for this use-case.

The same principle applies to checksums that are sometimes published for binaries - many still use MD5 or SHA-1 - and that's fine too, as (second) preimage resistance is what counts here, rather than collision-resistance.

Re: Disappearing messages for Signal

#157

Post by kelnos »

topkeks wrote: post #83
moxie wrote: post #74

Earlier quoted context omitted.

> Moxie has threatened to shut LibreSignal down if they allow LibreSignal users to message normal Signal users, and refused to even discuss alternative solutions. Please cite this. To my knowledge I never threatened anything, and your comment is a response to a quote from the discussion about LibreSignal, where I suggest that they submit a PR with the functionality they desire to Signal. Is that not an alternative? >…

kuschku BTFO

> If they can’t fork it while still using your servers, and you refuse to allow federation, how the FUCK is it open in any way?

"Open" doesn't mean you get to use someone else's servers. It just means that the code is there and you can make use of it in your app. There are a ton of things in that code that are valuable and useful as open source beyond the line that lists the URL of their servers.

Re: Disappearing messages for Signal

#158

Post by kuschku »

uph wrote: post #155
kuschku wrote: post #147

Earlier quoted context omitted.

> Please cite this. I’m sorry, what was this entire discussion then supposed to mean? https://github.com/LibreSignal/LibreSignal/issues/37#issueco... If they can’t fork it while still using your servers, and you refuse to allow federation, how the FUCK is it open in any way? How are users supposed to be able to verify the software running on their own systems when you only allow binaries compiled by yourself to commu…

> If they can’t fork it while still using your servers, and you refuse to allow federation, how the FUCK is it open in any way? What makes you think you have a right to demand federation? Run your own server if you don't like how they're doing it. You have access to the source under a Free Software license https://github.com/WhisperSystems but of course you don't want to actually do any work, you want to complain abo…

> What makes you think you have a right to demand federation? Run your own server if you don't like how they're doing it.

Because Moxie claims he wants to change mainstream communication?

You don't revolutionise mainstream communication by fragmenting your user base even more.

If every fork did what Moxie suggested, and create a completely new network, then soon there will be only a handful of users per network at all.

And users will just go back to Facebook or WhatsApp.

The claimed aim of Moxie is that everyone uses the same, partially safe, chat system.

The only merit Signal has over XMPP is that it aims to be used by everyone, including your grandma, trading adoption vs safety.

If that is the aim, you have to ensure it also is 100% compatible.

If you directly suggest to fragment the userbase, you are destroying the one single merit Signal has over XMPP with OMEMO.

Because then it becomes just another protocol for crypto nerds (and a worse one, in fact, considering the inclusion of Google code).

So, explain to me, how is fragmenting the userbase in any way conductive to the claimed aim?

Re: Disappearing messages for Signal

#159

Post by kuschku »

kelnos wrote: post #157
topkeks wrote: post #83

Earlier quoted context omitted.

kuschku BTFO

> If they can’t fork it while still using your servers, and you refuse to allow federation, how the FUCK is it open in any way? "Open" doesn't mean you get to use someone else's servers. It just means that the code is there and you can make use of it in your app. There are a ton of things in that code that are valuable and useful as open source beyond the line that lists the URL of their servers.

The whole point of Signal is that it trades a little bit of security away, and in turn you get something everyone can use.

If you fragment the user base, you throw exactly that away.

Because no user is going to be willing to install 20 Signal forks to talk to all their friends.

So, in practice, Signal is either at most visible source, or it's actually destructive to the average person's message security.

The only advantage Signal has over XMPP with OMEMO is the "everyone can use it, just works, everyone uses the same version" part.

Re: Disappearing messages for Signal

#160

Post by LeonidasXIV »

avhon1 wrote: post #112
moosingin3space wrote: post #97

Earlier quoted context omitted.

That is the issue I'm referring to.

How does re-sending the message help? Everybody in the group has already received the message a dozen times or more.

It doesn't but the sender does not know that everybody has the message a dozen times so he resends it.
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