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W3C Releases First Working Draft of Web Crypto API
From David Dahl's weblog: "Good news! With a lot of hard work – I want to tip my hat to Ryan Sleevi at Google – the W3C Web Crypto API First Public Working Draft has been published.
If you have an interest in cryptography or DOM APIs and especially an interest in crypto-in-the-DOM, please read the draft and forward any commentary to the comments mailing list: public-webcrypto-comments@w3.org"
This should be helpful in implementing the Cryptocat vision. Features include a secure random number generator, key generation and management primitives, and cipher primitives. The use cases section suggests multi-factor auth, protected document exchange, and secure (from the) cloud storage: "When storing data with remote service providers, users may wish to protect the confidentiality of their documents and data prior to uploading them. The Web Cryptography API allows an application to have a user select a private or secret key, to either derive encryption keys from the selected key or to directly encrypt documents using this key, and then to upload the transformed/encrypted data to the service provider using existing APIs."
Update: 09/19 00:01 GMT by U L : daviddahl commented: "I have built a working extension that provides 'window.mozCrypto', which does SHA2 hash, RSA keygen, public key crypto and RSA signature/verification, see: https://addons.mozilla.org/en-US/firefox/addon/domcrypt/ and source: https://github.com/daviddahl/domcrypt I plan on updating the extension once the Draft is more settled (after a first round of commentary & iteration)"
Anyone know which browsers & httpd's are planning support for this soon? Webkit?
Eventually at some point I would hope there's a backend server the app is talking to.
Why can't the server do it? Thin Client Fat Client... Why are you making my client fat Sir?
Sig. Sig. Sputnik
Just wondering how would you authenticate yourself with your browser? A username password authentication? If not, what would happen if someone else used your browser and had access to everything of yours?
Tired of my customary (Score:1)
No, The Cryptocat Vision statement explains it a lot better.
Basically it's for when your so paranoid that you fear even your cloud service app provider.
For example, you go and use Cloud Doc Editor and write some docs and save them locally...
But what about the remote server? What's it doing with that data? Is it making copies?
Could it know you write erotic fan-fic about Captain Picard having sex with Rainbow Dash?
Sig. Sig. Sputnik
Probably not. Encryption-in-the-DOM doesn't really do much for that (and, anyway, SSL client certificates for authentication do more for that, but almost no one uses them.)
It was because NearlyFreeSpeech doesn't support HTTPS, and I wanted to implement some sort of encryption. So, I figured that my server could encrypt pagelets and send them, and then the client could use a previously-established key to decrypt the pagelets, attaching them to the DOM structure in a logical way. The problem is, since JavaScript explicitly disallows XSS, I couldn't figure out a way to contact a separate key authority server. This meant that however I did it, I'd be (more) vulnerable to a man-in-the-middle attack.
Looking this over, it looks like this specification doesn't solve that issue. I know that key authorities can be compromised, but it's better to require two points of failure rather than one.
No it doesn't. It's just for crypto between server and client.
Microsoft releases less secure copy of W3C Web Crypto API already implemented in Internet Explorer 10 called SecureXaml while citing the changes as "features".
JavaScript doesn't "explicitly disallow XSS". Most browsers (through implementations of the still-in-draft Content Security Policy, and, for IE, additionally through its own "XSS filter") include means of restricting XSS, but those browsers also allow pages to control whether and how those XSS-limiting features are applied.
It's for a lot more than that. This API is specifying a full suite of cryptography tools. There's symmetric encryption, asymmetric encryption, signing, hashing, key generation, message authentication, secure random number generation...the works. You could use this API for anything you would want to use encryption for, showing what you want only to who you want and hiding it from everyone else. Even hiding it from the server if you want.
And yes, you could even implement something that would let you never type a password again.
You will create keypairs and exchange public keys via a web app. Via the API, you will be able to create digital signatures to help with user verification. This API is not being promoted as a silver bullet for security and privacy, however, when used in conjunction with other browser features like CSP ( http://www.w3.org/TR/CSP/ ) - and I imagine new browser features we still need to figure out (perhaps secure input and reading widgets), we hope to enable more secure web applications. I want to underscore that this API is just the first piece of the pie. Taming and being able to trust the DOM is not going to be easy.
They are never, ever good. Just more stupid crap that stresses me out and makes me tired.
boiled encryption, baked encryption, encription scampi, fried encryption, grilled encryption..encryption cocktails.
Douglas Crockford tends to disagree. And he's not alone.
How do they mitigate these inherent security problems of the JavaScript platform in the API draft? With XSS, I can always overwrite the browser's crypto API object, replacing it with a rogue implementation.
My understanding has been that JavaScript in its present form is not a viable platform for cryptography.
The API has two padding modes for RSA, PKCS#1v1.5 and OAEP. OAEP is provably secure. That is, if the underlying scheme (RSA) is a secure public key cipher, then RSA combined with OAEP is a semantically secure encryption scheme that is resistant to chosen-plaintext attacks. On the other hand, not only is PKCS#1v1.5 not provably secure, it has been known for years to be vulnerable to real world attacks.
Most of the time when you see people using it today it is for backwards compatibility, but in this case they are designing a brand new API. Why not go with the one which we know to be secure instead of encouraging the use of a dangerously vulnerable scheme?
... it's a bunch of random thoughts. Most of the current "draft" consists of "TBD" or "here are some ideas that need to be fleshed out". This looks like it's years from reality, at which point it'll have turned into another CDSA-sized monstrosity containing the union of every feature requested by every vendor ever.
I'd read that if it had a decent plot.
Basically it's for when your so paranoid that you fear even your cloud service app provider.
Maybe. The W3C draft lists "Cloud Storage" as one of its use cases, but remember that the app provider is also delivering the JavaScript that runs the decryption and loads up the DOM, so it could intercept the plaintext or decryption key if it wished. It doesn't protect against a malicious cloud service app provider, but it does make it easier for them to secure against data breeches (if their backups were stolen, for instance) and/or rely on 3rd party storage providers.
This has really interesting implications for online privacy, but the more practical/mundane benefits will be in reducing server CPU and making backend storage more secure.
-1, Too Many Layers Of Abstraction
Every time I read a story like this, I feel like we're getting closer and closer to the web browser implementing every feature of the OS.
Soon they will decide that they need a better way to manage tabs and build in a primitive tab manager, vaguely reminiscent of a window manager.
At some point there will be a page where you can enable and disable different extensions.
Some extensions will then open their own tab that will be handled by the tab manager.
Eventually we will decide that html is too restrictive, and someone will make an extension that translates some other markup language into html.
And so on, and so forth.
Finally, my stories about blue horsebird will be secured from the prying eyes of Google. This is truly a redletter day. /me uploads redletterday.md to the cloud
Well, there's encryption egg sausage and encryption, that's not got much encryption in it.
What?
I'm interested to see how this would work with the WebRTC API, to allow for browser-based encrypted P2P communications.
Couldn't see in the draft anything about crypto exportation restrictions. Would it be safe to use a browser supporting this in Iran?
sorry if you cant use aes then forget it....
Mandy Moore regrets every day of her life for discounting his prom request.
How you secure your keyring is upto you.
Most users will like the convienence of a single password model, but this time that password never leaves the device you are using. Still at risk to keyloggers just like before.
You could if you wanted secure your own secret keyring using a mixture of methods, such as a combined smartcard, password and biometrics. The biometric code unlocks data on a smartcard, the smartcard provides part of the data to the browser and the password entered into the computer completes all the necessary information needed to gain access to the keyring (that maybe stored on smartcard or on computers).
But the point is you get to decide how secure you want to make your keyring, you no longer have to hope the website you are using is understands how to do things securely. Also each website by default will have their own unique key and it is infeasable to brutre force the authentication.