Friday, May 13, 2011

BerrySync - Fifefox sync crypto, a step closer

BerrySync
To make a BerrySync compatible with FireFox Sync we need understand how sync connects to its servers. There are two challenges for me so far. First I opted to emulate sync's encryption steps  on the BlackBerry in Java, next I need to make a make a custom sync server and start talking to it before I start talking to the real thing.


FireFox Sync Crypto
So in order to even make sense of the data I'm getting back from the Sync Server I need to know what to do with it! I'm going to break down how I've understand Sync is expecting this to be handled.

  • When you sign up Sync makes a RSA 2048 bit key pair, that's whats used to encrypt during travel, I've been doing my reading here.
  • Decrypting
    1. Decrypt Weave Object with your private key
    2. Decode Base64 Weave payload to binary
    3. Decrypt payload binary with AES 256 bit key and 16 bit Initialization Vector, these are found in the Weave object
    4. Profit from here
Normally you would use Sync's client JavaScript to take care of this, however I attempted to port this to Java on the BlackBerry. Check out my encryption equivalent attempt of steps 2 and 3 here.Thankfully these algorithms are standardized and RIM's crypto library has had exactly what I've needed to far. I still need to confirm how BerrySync is going to handle the RSA keypair.


FireFox Sync Server
I'm at the point where I should start looking for my own custom firefox sync server, Seneca may have one. I was also going to set up one on my laptop this weekend using these:


So basically my goal for next Friday is to have access to a custom FireFox Sync Server and to iron out how BerrySync is going to handle the RSA key pairs. I want to be able to talk to a production Firefox server during the coming week!

No comments:

Post a Comment