Encrypted Social Network Vies For Disgruntled Facebook Users

angry tapir writes "With the look of Google Plus and Facebook-like elements, a new social network named "Syme" feels as cozy as a well-worn shoe. But beneath the familiar veneer, it's quite different. Syme encrypts all content, such as status updates, photos and files, so that only people invited to a group can view it. Syme, which hosts the content on its Canada-based servers, says it can't read it. "The overarching goal of Syme is to make encryption accessible and easy to use for people who aren't geeks or aren't hackers or who aren't cryptography experts," co-founder Jonathan Hershon said in an interview about the service." See also Diaspora.

1984 reference

[Anonymous Coward]

Syme—Winston's colleague at the Ministry of Truth, whom the Party "vaporised" because he remained a lucidly thinking intellectual. He was a lexicographer who developed the language and the dictionary of Newspeak, in the course of which he enjoyed destroying words, and wholeheartedly believed that Newspeak would replace Oldspeak (Standard English) by the year 2050. Although Syme's politically orthodox opinions aligned with Party doctrine, Winston noted that "He is too intelligent. He sees too clearly and speaks too plainly". After noting that Syme's name was deleted from the members list of the Chess Club, Winston infers he became an unperson who never had existed. Goldstein's book says that "Between the two branches of the Party there is a certain amount of interchange, but only so much as will ensure that weaklings are excluded from the Inner Party and that ambitious members of the Outer Party are made harmless by allowing them to rise." It is unknown whether Syme has been killed or promoted in the Inner Party in another province.

Re:Promises

[TheDarkener]

Except that they don't encrypt your data, you do. Probably would have helped to RTFA, huh bub? =p

Re:Who keeps the keys?

[mlts]

I can see two ways to do groups:

1: The group is a collection of private keys, so when one encrypts to Alice's group, in reality, Alice, Bob, Charlie, David, Elizabeth, and Frank have a key encrypted with their public keys and stored. The good about this is that the keys are secured, and there are no intermediate steps. The bad is that if Alice boots Charlie from the group and adds Mallory, stuff encrypted to the group is still readable by Charlie and not by Mallory until the object's core unlock key [1] is unlocked, the old names removed and new ones added.

The second is having the group have its own key, which is unlocked by Alice, Bob, etc. If someone is booted from the group, their user has the key removed from it. This makes things easier in not having to partially decrypt an object to add stuff, but it means one more key generated and possibly compromisable.

[1]: Most encryption uses a core symmetric key that is randomly generated, then encrypts that core key using the user's hashed passphrase, their public key, or both. Public key crypto is very rough on the CPU, so it is only used as little as possible, and in general, symmetric key algorithms are more secure than public/private key ones.

Re:Also

[aliquis]

They answered that themselves:
https://getsyme.com/about [getsyme.com]

So something like "not much, but at least we're trying."

Re:Promises

[CastrTroy]

Exactly. Reminds me of the stuff about Dropbox telling everybody their stuff was encrypted, and that even employees of Dropbox couldn't read the files. But it turned out that it wasn't true, and that files weren't actually being encrypted with the user's password, but with a single master key that was in the hands of Dropbox.

Re:What could go wrong?

[Opportunist]

So what? The threat from pedos is insignificant compared to the threat from politicians.

Re:Crypto in Syme may be unsound

[Kjella]

Note the commented-out line for strengthening the key. That looks like something was done to weaken the key generation.

More like the commented out code was done by someone who doesn't understand crypto and replaced by someone who did. PBKDF2 has a single purpose and that is to make password recovery from a hash difficult, this looks like it is negotiating a session key where it would be totally pointless since it's not based on a password at all.

To give you a very brief primer on PBKDF2:
In the beginning, people stored passwords in plaintext. That was stupid so they started hashing them with for example MD5, so instead of storing $password they'd store md5( $password ). Of course since the same password would end up having the same MD5 sum in every system, leading to rainbow tables. To counter this you add a salt and store md5( $password + $salt ). However, short passwords are quite few so it was still possible to loop through all of them in a short amount of time. So someone thought hey, why don't we just MD5 it again many times and store md5(md5(....(md5(md5($password + $salt))...)). PBKDF2 is basically a system for this, where you pick the hash function and number of iterations. Now testing a single password takes much longer, which is feasible to do on a single login but takes far too long to recover the passwords from a hash table by looping through all of them. So it is useful, but only for this specific purpose.