What to use Windows CardSpace for? - windows

I'm doing some funky authentication work (and yes, I know, open-id is awesome, but then again my open-id doesn't work right at this moment!).
Stumbling across Windows CardSpace I was wondering if anyone has used this in a real product-system. If you have used it, what were the pros and cons for you? And how can i use it in my open-id?

Umm no you don't; you can accept information cards on a web site using a cheap and cheerful certificate (but not self signed) or no certificate at all.
And yes, I've used it as part of a production system which grew out of a proof of concept I did at Microsoft.
Cons: If you don't have an EV SSL certificate you get warnings. The code for parsing a card is incomplete at best (you have to hack it around for no-SSL), you have to explain to users what one is.
Pros: Well that's more interesting; I was using managed cards and issuing them and then having 3rd parties use those to check claims; but for self issued cards; well, it's stronger than username password and doesn't have the same vulnerabilities OpenID has.

Related

Verifying clients when using interprocess communication

I'm building an application that will provide a service to other applications (let's pretend like it solves differential equations). So my DifEq service will be running all the time and a client application can send it requests to solve DifEqs at any point.
This would be trivial using sockets or pipes.
The problem is some applications nefariously want to send linear equations instead of differential equations, so I want to register applications that I know are sending proper DifEqs to my application.
Traditional sockets break down here, as far as I know.
Ideally, I'd like to be able to look at some information about the application that is making a request of me and (either through some meta-data on that application, through communication with my web site, or through some other, unkown method) determine it is an acceptable DifEq app. Furthermore, this ideal method would not be spoofable without a root/admin-level compromise of the underlying OS. If the linear equation app is also a root kit, I'll concede to being broken. :)
I need to be able to do this on Windows, OS X, and Linux (and maybe Android); but I recognize that it may not be the same solution on all platforms. So, how would you accomplish this (specify the platform you are focusing on, if appropriate)? I've done a lot of server-side development, but it's been way too many years since I've done any client-side development outside the browser and the world is very different today than it was then.
I think your question is a little confusing when it comes to talking about DifEQ vs LinearEQ.
It sounds to me like you are just looking for a routine way to verify that clients are authorized to connect. There is a lot to read up on this subject. Common methods would be to use SSL certificates to verify the identity of clients. You can also tunnel over SSH, or use OAUTH, etc, etc.
You'll have to do some more digging around the web to see what kind of authentication fits your scenario. You mention 'not spoofable'. I think that people generally end up compiling-in a certificate of private key into their application. This will stop all but the very dedicated and experienced hackers.

Protecting authentication data in WP7 app

I am writing a WP7 app and would like to include features to share highscore data using Amazon's AWS as storage service.
As far as I understand WP7 XAP files are (currently) safely encrypted and no known jailbreak for the phone exists. However, given that such a 'safe' encryption can be temporary, I would like to understand if/how this violates best practice.
AWS' dynamoDB uses temporary access tokens that can be generated using given account data and are valid for 36 hours the tokens must be verified using a signature with any request.
I am considering that all access data will be stored in the XAP file, which will also generate the temporary access token and signature. The information will be passed via https requests between the phone and AWS.
I was trying to work out alternative processes including passing the generation of the temporary token calculation to an external webservice, however I cannot think of a way to protect this data which would not be similarly compromised if the XAP file was accessible.
Am I missing the best practice approach completely or am I just overly cautious?
Thanks.
You won't ever be able to prevent users from sending false scores, pretty much for the same reason as unofficial cheating apps exist for every popular game. The best you can do is making it harder.
With a simple approach, the client sends the score directly to the server, without any kind of encryption. Someone can cheat just by running the app on the emulator and capturing the outgoing packets, then opening the same URL on his desktop browser. Estimated time: less than 10 minutes, and it can be done by anyone who knows that he can download XAPs directly from the marketplace, remove the manifest, and deploy it on the emulator.
Then you can add an encryption key on the client. Now someone has to know C# and Reflector to extract it, but it's still easy for someone having those skills.
Next level, you can add an encryption key AND obfuscate the assembly. Knowledge of CIL and Relector are required to extract the key. It'll take 30 minutes to an hour to a highly skilled developper to extract the key, and many hours for most developpers.
Finally, you can add multiple steps to confuse even more the intruder (for instance, downloading a temporary token from a server and using it somehow in the score sending process). Also, you can design the scoring system in a way that some scores are illegal (dumb example: if the minimal scoring action earns 2 points, then if someone sends an odd number as a score you know he's cheating. This one is easy to figure out, but you can make much more complex rules).
In any way, keep in mind that your system will always be vulnerable, it's only a matter of how much time it will take to the attacker to break through it. If it takes many hours or days to a highly skilled developer, then unless you're offering some worthy prize to the best player, you can safely assume that nobody will bother doing that.

In need of a practical certificate tutorial/overview

Can anyone recommend me an overview about certificate management? I'm a big "learn from Wikipedia" type of guy but the relevant data there is general information on public-key cryptography, and I'm looking to map that to practical knowledge about how certs are used (web browsing, exchange of business messages, etc.)
I don't need super-detailed information at this point, but I'm looking for a general overview about things like:
File types one would expect to see, and what kind of information they contain
How certs are organized and "chained"
What certs are used for - I generally understand the basics like signing and encryption, but I know they're used for a lot more than that. For example, how are certs used in web browsing or (to validate a site), or HTTPS (to secure transmission)?
I'm a Windows guy, so information about the way certs are organized and used in Windows (the cert store) would be helpful as well.
Thanks!

User security in the database of my website

Lets say i have a website mysite.com that will store some sensitive personal data (bank related)
On this website i have an oracle database with a USERS tables that will store the logins and passwords of users from mysite.com
I have a few questions :
How should i store passwords,encryption of course, but which ?
What should be the process for registration ? send an email to confirm is really necessary ?
Any good advices on login processes in general ?
For information, i m using Oracle APEX
You're storing bank related sensitive personal data. Don't hack your own solution. Use an existing, proven solution. Most likely you will also be running into all kinds of security and privacy laws, regulations and liabilities when dealing with such data. Find someone who knows these regulations and who can help you and advise you.
Don't try to do this yourself. "Anyone can build a security system they they themselves cannot break." - I think that's a Bruce Schneider quote. Heed it.
Edit to react on comment:
Even when dealing with private finance software you're probably dealing with bank account numbers, social security numbers, etcetera. So you are probably still running into various kinds of regulations.
Systems like OpenID and Oracle SSO only cover authentication. Regulations also dictate minimum security measures on how you should store data in your database, how you should treat backups, how you should deal with people (e.g. developers) accessing the database, etcetera, etcetera. If you don't follow these and something goes wrong, you're liable.
I really urge you to seek help from someone knowledgeable in the field. Explain them what you want to do, what you want to store, etcetera. They can tell you what (if any) regulations apply. Only then can you start looking at how you are going to implement this and what off-the-shelf components you can use.
Under no circumstance should a password be encrypted. The use of encryption implies that there is a decryption function and that would be a violation of CWE-257. Passwords must always be hashed, and SHA-256 is an excellent choice. The password should be salted with a cryptographic nonce. Authentication systems are highly simplistic when taking into consideration the other security systems you rely on.
You must be VERY CAREFUL to make sure that your system is free of SQL Injection. I recommend obtaining a copy of Acunetix($) NTO Spider ($$$) or wapiti(open source). In any case parameterized quires is the way to go.
Take a look at the answers to this question.
Passwords should be stored as a salted hash. Use a unique salt for each. For hashing there are better alternatives but SHA1 is alright for many purposes (its available via DBMS_CRYPTO). Even better go for SHA256 (using http://jakub.wartak.pl/blog/?p=124).
User registration confirmation really depends on the site. If you want to get users in quickly then you could allow them in after registration for a limited time until they click the activation link. All the activation really gets you is a real email address to associate with the user. Also consider captcha to prevent automated/scripted sign-up.
Login should enforce temporary lockout after some invalid attempts (and alert admins when successive lockouts are hit). Enforce a password complexity too.
OWASP has very good general advice on secure web app design.
Wikipedia has some information on Oracle Apex Security. Another comment suggested a web testing tool such as Acunetix or NTO Spider (I would suggest Burp instead), there is also a tool for testing the security of Apex applications through analysis of the source (ApexSec) - (disclosure, I work for this company).
You could also consider a third-party view on you application, be that penetration testing or code review. A Web Application Firewalls can provide some value depending on your context.

is it reasonable to protect drm'd content client side

Update: this question is specifically about protecting (encipher / obfuscate) the content client side vs. doing it before transmission from the server. What are the pros / cons on going in an approach like itune's one - in which the files aren't ciphered / obfuscated before transmission.
As I added in my note in the original question, there are contracts in place that we need to comply to (as its the case for most services that implement drm). We push for drm free, and most content providers deals are on it, but that doesn't free us of obligations already in place.
I recently read some information regarding how itunes / fairplay approaches drm, and didn't expect to see the server actually serves the files without any protection.
The quote in this answer seems to capture the spirit of the issue.
The goal should simply be to "keep
honest people honest". If we go
further than this, only two things
happen:
We fight a battle we cannot win. Those who want to cheat will succeed.
We hurt the honest users of our product by making it more difficult to use.
I don't see any impact on the honest users in here, files would be tied to the user - regardless if this happens client or server side. This does gives another chance to those in 1.
An extra bit of info: client environment is adobe air, multiple content types involved (music, video, flash apps, images).
So, is it reasonable to do like itune's fairplay and protect the media client side.
Note: I think unbreakable DRM is an unsolvable problem and as most looking for an answer to this, the need for it relates to it already being in a contract with content providers ... in the likes of reasonable best effort.
I think you might be missing something here. Users hate, hate, hate, HATE DRM. That's why no media company ever gets any traction when they try to use it.
The kicker here is that the contract says "reasonable best effort", and I haven't the faintest idea of what that will mean in a court of law.
What you want to do is make your client happy with the DRM you put on. I don't know what your client thinks DRM is, can do, costs in resources, or if your client is actually aware that DRM can be really annoying. You would have to answer that. You can try to educate the client, but that could be seen as trying to explain away substandard work.
If the client is not happy, the next fallback position is to get paid without litigation, and for that to happen, the contract has to be reasonably clear. Unfortunately, "reasonable best effort" isn't clear, so you might wind up in court. You may be able to renegotiate parts of the contract in the client's favor, or you may not.
If all else fails, you hope to win the court case.
I am not a lawyer, and this is not legal advice. I do see this as more of a question of expectations and possible legal interpretation than a technical question. I don't think we can help you here. You should consult with a lawyer who specializes in this sort of thing, and I don't even know what speciality to recommend. If you're in the US, call your local Bar Association and ask for a referral.
I don't see any impact on the honest users in here, files would be tied to the user - regardless if this happens client or server side. This does gives another chance to those in 1.
Files being tied to the user requires some method of verifying that there is a user. What happens when your verification server goes down (or is discontinued, as Wal-Mart did)?
There is no level of DRM that doesn't affect at least some "honest users".
Data can be copied
As long as client hardware, standalone, can not distinguish between a "good" and a "bad" copy, you will end up limiting all general copies, and copy mechanisms. Most DRM companies deal with this fact by a telling me how much this technology sets me free. Almost as if people would start to believe when they hear the same thing often enough...
Code can't be protected on the client. Protecting code on the server is a largely solved problem. Protecting code on the client isn't. All current approaches come with stingy restrictions.
Impact works in subtle ways. At the very least, you have the additional cost of implementing client-side-DRM (and all follow-up cost, including the horde of "DMCA"-shouting lawyer gorillas) It is hard to prove that you will offset this cost with the increased revenue.
It's not just about code and crypto. Once you implement client-side DRM, you unleash a chain of events in Marketing, Public Relations and Legal. A long as they don't stop to alienate users, you don't need to bother.
To answer the question "is it reasonable", you have to be clear when you use the word "protect" what you're trying to protect against...
For example, are you trying to:
authorized users from using their downloaded content via your app under certain circumstances (e.g. rental period expiry, copied to a different computer, etc)?
authorized users from using their downloaded content via any app under certain circumstances (e.g. rental period expiry, copied to a different computer, etc)?
unauthorized users from using content received from authorized users via your app?
unauthorized users from using content received from authorized users via any app?
known users from accessing unpurchased/unauthorized content from the media library on your server via your app?
known users from accessing unpurchased/unauthorized content from the media library on your server via any app?
unknown users from accessing the media library on your server via your app?
unknown users from accessing the media library on your server via any app?
etc...
"Any app" in the above can include things like:
other player programs designed to interoperate/cooperate with your site (e.g. for flickr)
programs designed to convert content to other formats, possibly non-DRM formats
hostile programs designed to
From the article you linked, you can start to see some of the possible limitations of applying the DRM client-side...
The third, originally used in PyMusique, a Linux client for the iTunes Store, pretends to be iTunes. It requested songs from Apple's servers and then downloaded the purchased songs without locking them, as iTunes would.
The fourth, used in FairKeys, also pretends to be iTunes; it requests a user's keys from Apple's servers and then uses these keys to unlock existing purchased songs.
Neither of these approaches required breaking the DRM being applied, or even hacking any of the products involved; they could be done simply by passively observing the protocols involved, and then imitating them.
So the question becomes: are you trying to protect against these kinds of attack?
If yes, then client-applied DRM is not reasonable.
If no (for example, you're only concerned about people using your app, like Apple/iTunes does), then it might be.
(repeat this process for every situation you can think of. If the adig nswer is always either "client-applied DRM will protect me" or "I'm not trying to protect against this situation", then using client-applied DRM is resonable.)
Note that for the last four of my examples, while DRM would protect against those situations as a side-effect, it's not the best place to enforce those restrictions. Those kinds of restrictions are best applied on the server in the login/authorization process.
If the server serves the content without protection, it's because the encryption is per-client.
That being said, wireshark will foil your best-laid plans.
Encryption alone is usually just as good as sending a boolean telling you if you're allowed to use the content, since the bypass is usually just changing the input/output to one encryption API call...
You want to use heavy binary obfuscation on the client side if you want the protection to literally hold for more than 5 minutes. Using decryption on the client side, make sure the data cannot be replayed and that the only way to bypass the system is to reverse engineer the entire binary protection scheme. Properly done, this will stop all the kids.
On another note, if this is a product to be run on an operating system, don't use processor specific or operating system specific anomalies such as the Windows PEB/TEB/syscalls and processor bugs, those will only make the program even less portable than DRM already is.
Oh and to answer the question title: No. It's a waste of time and money, and will make your product not work on my hardened Linux system.

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