CyanogenMod Integrates Text Message Encryption 118
sfcrazy writes "People are now more concerned regarding their privacy after discovering about efforts made by governments to spy on their communications. The most practical solution to keep messages, emails and calls secure is to use a cryptographic encryption mechanism. However, just like the name of the method, the installation process is complex for most users. To solve this, CyanogenMod will come equipped with built in encryption system for text messages."
Whisper System has integrated their TextSecure protocol into the SMS/MMS provider, so even third party sms apps benefit. Better yet, it's Free Software, licensed under the GPLv3+. Support will debut in Cyanogenmod 11, but you can grab a 10.2 nightly build to try it out now.
Key exchange (Score:5, Interesting)
The most important part of any crypto communication system is key exchange. Looks like this protocol uses automated SMS key exchange, and implementations should store keys similar to SSH. It's trivial to MITM, but it's a high risk attack because people can simply meet in person to compare keys.
Other problems (not MITM but end-to-end) (Score:5, Interesting)
It's trivial to MITM, but it's a high risk attack because people can simply meet in person to compare keys.
Avoiding MITM has been successfully solved using the Socialist Milionaire [wikipedia.org] problem.
At most, 2 contacts need to call (voice) each other and compare a bunch of keywords. From that point onward, their communication can be trusted.
I see another problem:
The best (and nearest-to-perfect) secure solution requires end-to-end encryption. (the absolute first and last application on the chain to the encryption / decryption. Encryption is done on the first ever software getting the message, decryption is done on the last software drawin the message on the screen)
But CyanogenMod's implementation isn't end-to-end. They instead have integrated crypto in the SMS messaging service of the OS. ... These 3rd party app could actually be spying.
The intention is noble: You're not forced to use CyanogenMod's SMS App. You could use Skype or Facebook chat app (as long as the app supports handling SMS in addition to other communication)...
The main problem is easy to spot:
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**Acquiring the shared secret is the problem, not verifying whether someone else also has the secret.**
but you don't need a shared secret, what you need is to verify that the public key is really from the other guys phone.. and not from a mitm bot.
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But CyanogenMod's implementation isn't end-to-end. They instead have integrated crypto in the SMS messaging service of the OS. ... These 3rd party app could actually be spying.
The intention is noble: You're not forced to use CyanogenMod's SMS App. You could use Skype or Facebook chat app (as long as the app supports handling SMS in addition to other communication)...
The main problem is easy to spot:
Same for CyanogenMod itself. Who says this addition hasn't been implemented by an NSA employee, backdoor and all?
Use the Source, Luke! (Score:4, Informative)
Same for CyanogenMod itself. Who says this addition hasn't been implemented by an NSA employee, backdoor and all?
Except that CyanogenMod itself is opensource.
You check the source yourself, and the source is seen by lots of other people. If there's a backdoor in there, someone is bound to see it.
Even if some NSA employee managed to use social engineering to sneak in an exploitable-bug while submitting a patch to improve otherwise the code, someone will end up noticing it. (e.g.: Both Debian and Android have had, at some point of time, a broken DSA generation which produced predictable key. Nonetheless, in both case the defect was noticed and corrected).
That's the whole point of RMS' rant about free and opensource being a necessity for security. If the source is open, you don't have to specifically trust the author of the source (who might either be a mole or clumsy and end up making bugs). You can instead trust the community (Debian, Android), or you could check it yourself (I'm able to do *some* light code reviewing for a few of my coding needs), or pay someone to do the checks for you (TrueCrypt is exactly getting this treatment, crowd funding style).
And even if you don't compile your binaries yourself and doubt about the binaries offer as downloads by the CyanogenMod team (perhaps the binary you download contain a backdoor that isn't in the source), several tools are here to help too:
- GPG-signing of binaries (so you know the binary you got was actually from CyanogenMod and not one of the relay of NSA which ended up serving you a booby-traped binary, exactly like their slashdot clone)
- Deterministic build (a way for several independant people to check that the binary you have are produced from the official source and not by some NSA mole inside CyanogenMod who is injecting a backdoor before publishing them. It's used by Tor, Bitcoin, etc. It's being implemented for TrueCrypt too)
- Differential build (each time there's a discussion about trusting the source, there's always someone coming up with this old paper of C's author about booby trapped self-replicating compiler. And completely forgot that the author himself proposed a way to detect such booby-trapped shit. Not that this was ever seen in the wild. But in theory it's evitable, with these technique).
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TrueCrypt is exactly getting this treatment, crowd funding style.
After how many years? Truecrypt has been out for a decade, meets the definition of open source, and despite its relatively modest size is only now receiving audit to see if the source can be trusted and that the binaries everyone has been using were actually built from it.
As such I wouldn't hold much faith that just because Cyanogenmod is open that suddenly it's more secure than a proprietary product. It might be and open source is good for a raft of reasons, but I suspect anyone who wanted to throw an ex
No magic, requires efforts (Score:2)
As such I wouldn't hold much faith that just because Cyanogenmod is open that suddenly it's more secure than a proprietary product. It might be and open source is good for a raft of reasons, but I suspect anyone who wanted to throw an exploit could still bury it in plain sight if they wished.
No, indeed. Being opensource doesn't make CyanogenMod automagically secure. GPL and BSD license, aren't magic pixie dust, per se.
BUT being opensource at least make it 100% possible to audit CyanogenMod (unlike say, iOS. Even if you wanted you couldn't audit that one, because its source code is a well guarded secret by Apple).
If you're not content with approach of "let's wait. if there's something evil inside, someone is bound to discover it eventually, some day", YOU CAN DO something about it.
1. Either have
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There is still yet another reason to trust OpenSource code, risk of being exposed. If you're the NSA, and you're inserting illicit code into Open Source, then you're at a very high risk of being exposed as a mole. This risk, being a known mole is too high for a "real" spy. If I were a spy agency, I wouldn't risk any assets for such a short term gain. Once exposed, a mole will have no trustworthiness AND all associations would likely become suspect. Basically, you're risking the whole operation on the assump
Non-obvious (Score:2)
Combined with the above, these two assumptions (risk of exposure, looking for compromises) is sufficient to take the approach that the code is not likely compromised on purpose. This is not to say, that there are no risks, just that they aren't likely to be intentional.
Either that, or the backdoors are much more sophisticated and designed to look like genuine errors once discovered.
Probably would look much more like something out of the "Underhanded C Code Contest [xcott.com]" than an explicit "If (NSA_flags == ture) then send_to(NSA, data);"
In theory, someone with half a clue would notice that putting backdoors has 2 very strong disadvantages:
- a bug exploitable by your guys is a bug exploitable by Russian/Chinese/etc. a hidden backdoor in software used by US civilians also makes th
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This risk, being a known mole is too high for a "real" spy. If I were a spy agency, I wouldn't risk any assets for such a short term gain. Once exposed, a mole will have no trustworthiness AND all associations would likely become suspect.
And the solution to that problem is easy. Money. Well money and indirection.
Most people can be bought for a price and they don't have to know it's the NSA doing the buying, it could be a terrorist group or something more benign. All that matters is there is not direct link between the code submitter and NSA. Heck, the submitter can claim the NSA made him/her do it as long as they come off as a crazy person (which they will with no direct proof.. "well this person paid me to submit this code, no they didn'
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Today, we are launching our version initially into the CM 10.2 nightly stream to test the server load and make sure things are working at scale. Once things are dialed in, we’ll also enable this for CM 11 builds moving forward.
Depending on how it's implemented, the whole system [github.com] may depend on a central server that facilitates the initial key exchange (prekeys). That, in itself, seems like a massive compromise vector. Why should users need to trust a third party server for key exchange? It'd be much better to use a system like ZRTP where the users are expected to compare fingerprints out of band.
There is a method of key exchange that doesn't use the server (KeyExchangeMessage), but it isn't clear whether the user gets to choose whi
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Depending on how it's implemented, the whole system may depend on a central server that facilitates the initial key exchange (prekeys).
From the WhisperSystem posting:
The Cyanogen team runs their own TextSecure server for WhisperPush clients, which federates with the Open WhisperSystems TextSecure server, so that both clients can exchange messages with each-other seamlessly.
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Wait, wait, wait. If they federate with some other service, why not federate it with XMPP networks? AFAIK TextSecure uses OTR or some variation of it. And if you make it talk to other xmpp servers out there it's not yet another messenger, it's a step towards future.
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Both people just need to swap public keys first.
There's the problem, right there...
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if I store all encrypted messages and at some point I compromise the pgp key, I get access to all past/future -assuming you don't notice-- messages. In the case of their system if I compromise a key I get access to 1 message
https://whispersystems.org/blog/asynchronous-security/ [whispersystems.org]
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So you won't mind me installing cameras in your house and tapping all your phones then?
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Because I definitely do not want the .gov overstepping their boundaries and ignoring my right to personal privacy. They have no reason to peek in and look at my personal life when I've done nothing wrong.
The problem is needing to protect oneself from un-Constitutional violations of the BoR by an obviously power-mad ruling elite in the first place.
With the immense resources of the US government available and few if any restrictions to methods, if the TLAs want in, they'll get in.
Until the size & power of government and the bureaucracy are massively rolled back and accountability plus term limits enacted and enforced, it's a losing game. They'll get to whomever they need to get to to make sure their abili
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The problem is that our current bureaucracy is such that it inherently protects the ruling elected class from accusations of tyranny, while providing the services needed to be a tyranny. This is why the players change from Republican Tyrants to Democrat Tyrants, giving the illusion accountability. There is no accountability. The whole IRS, Benghazi, ObamaCare, Patriot Act etc etc etc going back to Nixon proves this. Nixon was held accountable, because he went beyond the Bureaucracy's protection.
The only fix
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Re:I personally find this very important... (Score:5, Interesting)
How do you feel about the private contractor that's doing the snooping knowing what you've had for dinner and that your wife has breast cancer and selling that information to companies who can now try to sell you miracle cancer cures? How comfortable are you with prospective employers knowing your child has autism and needs extra attention, which might possibly mean more absences from work?
Remember, most of the data collection and first-level analysis is not done by "the government" but by a private company that works for the government. And, that private company has corporate clients besides the government. How comfortable are you knowing that anyone who can afford to pay having access to all your personal communications?
And what happens that day you disagree with what the government is doing? How comfortable are you knowing that you're planning to go to a political demonstration? How comfortable are you with your boss or potential employer knowing?
How comfortable are you with a techie with anti-social tendencies having access with all your family's communication? Your wife's, your daughter's? Because who do you think is working for that private contractor who's working for the government?
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And what happens that day you disagree with what the government is doing?
This.
People who agree with what the NSA and pals are doing believe in a fair and stable government, but what if it changes? What if suddenly your rulers become tyrants?
It's not like it's never happened before in history.
At that point, even if you can stop the data collection, it's already too late. They've already got all of your past history. Suddenly, something which may be innocuous to today's society may be a death sentence in tomorrow's.
What strikes me most is to hear many of the same people asking for
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We are already ruled by tyrants, they are the Bureaucracy. Try to fire them and see how tyranny works.
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"'With the first link, the chain is forged. The first speech censured, the first thought forbidden, the first freedom denied,
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Hard to take CM privacy concerns seriously (Score:4, Interesting)
Even before the buyout, the CM team refused patches to basically integrate pdroid into the mod, for fear of "angering developers." So even if something like this works, all the bad guys have to do is hit up the app market for the data it's sucking up anyway.
Re:Hard to take CM privacy concerns seriously (Score:4, Insightful)
That's kind of a re-invention of history. CM simply didn't integrate pdroid because it was a support nightmare waiting to happen. At the time of the pdroid discussion, Steve said that they were already working on a bunch of privacy features that would meet the usability standards they were aspiring to... and here we are.
Don't forget that this message encryption follows on from the App Privacy Mode that they have successfully deployed since then (and makes much of pdroid redundant). They are taking a measured and transparent approach to privacy. Just as a serious organisation should..
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That's not what the mailing list said. And no, the current offerings don't come even close to pdroid, or "enough", for that matter. It's pitiful theater at best.
Re: Hard to take CM privacy concerns seriously (Score:1)
There was a time when trolling was an art.
In my day, we crafted clever well-written responses with a single link that supposedly contained more information but was actually a photo of a man stretching his rectum with both hands.
The next generation of trolls was more nostalgic and reached into the previous generation's culture to find a goofy music video to link to. Not very imaginative but at least it could be considered an homage.
This generation...your generation, has passed on the entire idea of the cleve
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Spy vs Spy (Score:5, Interesting)
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You show...good but not total understanding. In current systems this works.
In past systems this has been handled.
See mixmaster, remailers, etc.
If whisper does this right, what people know is "35 messages go into mixmaster3 at time t" and "15 messages go out of mixmaster3 to mixmasters 1..n at time t+1" and "16 go out to realworld addresses A1...Ai"
A good enough tumbler chain crushes most metadata analysis for short messages, provided you'll live with limited message loss, and a bit of latency that makes re
Re:Spy vs Spy (Score:5, Insightful)
Seriously, why are The People trying to play Spy vs Spy with their own government? The government owns the internet. It's as silly to encrypt your license plate as it is your text messages. You have no way to do so. If you're able to send a text, then you're using a carrier of some kind. That carrier has no control over the government's ability to get the data if the government wants to.
Isn't that the whole point of this project? It allows you to encrypt your data, so unless you think the government has a secret back door into every encryption algorithm, when you encrypt your data, the government can't see it. They may still be able to see who you're talking to (a TOR-like extension might help), but they won't know what you're saying unless they compromise your phone (or happened to compromise the key exchange).
Remember, it's metadata that we're talking about. "Who talked to who - and what time(s)". Linking people together is what it's all about. They don't need to know what you're talking about, so long as they know who you're talking to.
Despite what the NSA wants you to think, it's not just "Metadata" -- any analyst who believes that a conversation is with a foreign correspondent can retrieve the entire contents of the conversation -- text, email, etc with nothing more than a slightly better than 50% belief that one party in the conversation is foreign. No warrants or other oversight required.
Do you think the government should be able to retrieve your private conversations on an analyst's "hunch"?
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Do you think the government should be able to retrieve your private conversations on an analyst's "hunch"?
Yes
That's clever coming from an Anonymous Coward, but you should feel free to bcc AnyAnalyst@NSA.gov on all of your emails.
But I'd rather keep my conversations private.
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Actually, this is a clever sort of attack. It is the one where every public email address of the goverment becomes a spam bucket of inane email conversations, such that if you include them in the BCC field for every email you send, it overwhelms these in boxes with more stuff than they can troll through, making it completely useless.
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Do you think the government should be able to retrieve your private conversations on an analyst's "hunch"?
Not at all, I think the whole thing is total bullshit, beyond expression and pushes the bounds of humanity itself. However That means nothing to anyone but me, maybe some others. What our government needs is some small, no matter how small, reason to point a finger. Don't forget, the whole war in Iraq started because of a "hunch". And they found out that that hunch was wrong. Well... the wars (yes wars) machine keeps on turning, brother.
...so unless you think the government has a secret back door into every encryption algorithm...
Where have you been man? See here [techreport.com].
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...so unless you think the government has a secret back door into every encryption algorithm...
Where have you been man? See here [techreport.com].
There's a big difference between a backdoor in a published encryption algorithm and a backdoor in commercial encryption software/hardware. It's much harder to hide a backdoor in a well known algorithm that's been under international scrutiny. Though I do have my doubts about the ECC constants [stackexchange.com]
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It is
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The Importance of Metadata (Score:2)
The Importance of Metadata:
It is not Who you know, or What you know, or even What you know about Who you know.
It is Where is Who, that provides the targeting for the missile.
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Playing Spy vs Spy with the government is a form of democratic control of things related to you. That control has been lost to agencies and bureaucrats. There should be a trusting relationship, but the trust is broken. The trust itself is based on an empty facade, which was effectively proven by Snowden (and others..). The power is an illusion. In the end an individual can independently act regardless of the conditioning.
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The principles of safety and privacy do not require an accident before hand to be recognized.
Actually, most safety and security activities are the direct result of an attack or accident. For example, traffic signals are usually erected at unsafe intersections only after a certain number of severe accidents. Sony didn't encrypt their users' passwords in their database, even though hacking of it has been a very real possibility for many years (and I'm only presuming they've encrypted it since the leak.) The world (except for Israel) didn't get truly strong airline security until after the September 1
They're already tracking us in WoW (Score:1)
I don't see the point, since the encryption methods are probably also hacked, and we probably has OS libraries with whisper routines that just invoke built into our devices.
All the backdoors are wide open, and the front doors too. We live in Stasi Germany.
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I've seen little suggesting the NSA has been breaking much crypto at the algorithm level...most of what I've seen in the leaked materials has suggested more in the way of mitm attacks (sometimes through key forgery, as the NSA essentially has root certificate authority). The public key side of this of course still leaves that possibility entirely open if one doesn't take care to do a secure key exchange, but it's still a step in the right direction.
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comment. Answer: maybe you are more desperate than him. A shallow answer. Morale: let's be sure
we're all on the same side and do something on the technical as well as the political level.
Hello world (Score:1)
One minor part in a bigger problem. (Score:1)
Key distribution and metadata? (Score:2)
I looked at this, and there are 2 things I can't understand:
1. How does key distribution work? Even public-key crypto of this type doesn't necessarily work if there is a man in the middle.
2. How is metadata protected? For an SMS, often the timestamp and sender/recipient pairing is as revealing as the message content.
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From what I gather the encryption scheme is vulnerable to MITM attacks, and doesn't do anything about metadata.
Every message is encrypted with a unique key so if they MITM a conversation they'll only get that conversation's data.
MITM isn't hard for agencies like the NSA, but it takes a hell of a lot more effort than passive taps.
The idea isn't to prevent a targeted attack, the idea is for users to prevent large scale data collection.
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RTOS on the chip that controls wireless, etc. (Score:3, Interesting)
Utility of text messages (Score:2, Troll)
Text messages are useful because they're banal. "I'll be late" "pick up milk" "what section are you sitting in?" "when do we need to leave?" If you're committing any relevant content to SMS you have different problems that security isn't solving.
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It does work. You just have to RTFM and set it up properly.
How keys are managed (Score:5, Informative)
The TextSecure Protocol
TextSecure's upcoming iOS client (and Android data channel client) uses a simple trick to provide asynchronous messaging while simultaneously providing forward secrecy.
At registration time, the TextSecure client preemptively generates 100 signed key exchange messages and sends them to the server. We call these "prekeys". A client that wishes to send a secure message to a user for the first time can now:
Connect to the server and request the destination's next "prekey."
Generate its own key exchange message half.
Calculate a shared secret with the prekey it received and its own key exchange half.
Use the shared secret to encrypt the message.
Package up the prekey id, the locally generated key exchange message, and the ciphertext.
Send it all in one bundle to the destination client.
The user experience for the sender is ideal: they type a message, hit send, and an encrypted message is immediately sent.
The destination client receives all of this as a single push notification. When the user taps it, the client has everything it needs to calculate the key exchange on its end, immediately decrypt the ciphertext, and display the message.
With the initial key exchange out of the way, both parties can then continue communicating with an OTR-style protocol as usual. Since the server never hands out the same prekey twice (and the client would never accept the same prekey twice), we are able to provide forward secrecy in a fully asynchronous environment.
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PFS only if you trust the server. Haven't we seen the "trust the server"-concept a few times too much lately?
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and the cost? (Score:1)
So now your 20 character "just on the way home" text message blows out to a couple of thousand bytes, and your telco provider has to send your SMS as 10 SMS now, and charges your accordingly.
Code quality? (Score:2)
Encrypting your stuff is all good and nice, but you should use a piece of software that has been written using established secure coding standards. Just because it's open source doesn't mean it's also secure (cf. PHP, OpenSSL). Rather, being open source is a necessary, but not a sufficient criterion in the evaluation of security-critical applications.
Given the track record [f-droid.org] of this particular application, I'm a bit skeptical whether one should really use it for anything serious.
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Hmm. I feel OK about trusting someone who understanding encryption standards sufficiently well to to identify SSL implementation bugs in major browsers (and construct exploits for them) working on encryption software that I use.
What I got out of the F-Droid conversation was that someone complained about a bug (which they overstated) that had already been fixed, and because Moxie himself wasn't publishing to F-Droid the version on it didn't get updated.
CM11 nightlies also include it (Score:1)
Here .. let me fix that for you (Score:2)
There .. that's more accurate....