we are saving user data on a server and we want to do save this data encrypted with TrueCrypt.
If a user registers, we generate an asymmetric key for him that is encrypted with his password. This asymmetric user-specific key will encrypt all the keys that are used for services, including the above mentioned data encryption.
If we now want to read the users files, add new and modify existing ones from within our Java Application running on a Application Server, should we mount the TrueCrypt container?
We think that it might be a security leak as an attacker could easily look in the mounted container, but we also have no other idea - we are kind a stuck!
I am sure someone can help us here.
Thanks,
Heinrich
#edit By the way, we are using Spring for your Java App.
I don't think it is a good idea to use TrueCrypt for this usecase. When using TrueCrypt you have no other choice than mounting it on each request to encrypted files. You should think about using plain Java encryption and do encryption and decryption yourself. There are libraries like Google Keyczar that may help you implementing this.
Related
Hello to all
I did a lot of research on encrypting important data such as credit card numbers in Spring Boot, and three ways to securely encrypt data caught my attention:
Protect secrets with Hashicorp Vault
Column-level encryption
Data Encryption with Java Cryptographic Extensions
All three methods have their advantages and disadvantages. The initial setup of the vault requires a lot of configuration, and I could not find a complete and integrated source for learning it. Column-level data encryption imposes a large processing load on the server, and requires the management of cryptographic keys. The third case requires the creation, management and maintenance of encryption keys for each client request. Is there a better choice for managing sensitive customer data such as email addresses or credit card numbers? Or is it recommended to use Vault to manage the secrets of website users?
Can I encourage you to take a look at our product. I don't want this to be a shameless plug but as a developer who has felt your pain, I think you would want to take a look at what we have. We have designed it to address some of your concerns. ubiqsecurity.com.
To address your specific considerations.
MUCH easier than setting up Hashicorp Vault. We have demos of creating an account and sharing encrypted data in two different languages within 5 minutes. The demos should help you get started if necessary but I wouldn't expect you to need them. Our client libraries also have fully functional examples to help you get started.
This seems to be the reason DBAs are hesitant to turn on encryption within the DB layer. We are leaving the encryption at the application layer. If your encrypted DB is up and running and someone is on the DB server with harvested credentials is your DB really secure?
We manage encryption keys for you. Client uses an API key (similar to other SaaS). Data is encrypted on the client.
Please feel free to reach out to us if you have any questions. Again, not trying to be a shameless plug, but we know the problems developers face when working with encryption and feel our solution addresses a number of the issues you are facing as well as others you haven't even mentioned.
Are there any examples of using encryption to encrypt the disk-cache used by OkHttp's HttpResponseCache? Naively, I don't think this is a very hard thing to do, but I'd appreciate any advice or experience to avoid security-pitfalls.
Without too many specifics, here's what I'm trying to achieve: a server that accept user's api-keys (typically 40-character random string) for established service X, and makes many API calls on the users behalf. The server won't persist user's api-keys, but a likely use case is that users will periodically call the server, supplying the api-key each time. Established service X uses reasonable rate-limiting, but supports conditional (ETag, If-Modified-Since) requests, so server-side caching by my server makes sense. The information is private though, and the server will be hosted on Heroku or the like, so I'd like to encrypt the files cached by HttpResponseCache so that if the machine is compromised, they don't yield any information.
My plan would be to create a wrapper around HttpResponseCache that accepts a secret key - which would actually be a hash of half of the api-key string. This would be used to AES-encrypt the cached contents and keys used by HttpResponseCache. Does that sound reasonable?
Very difficult to do with the existing cache code. It's a journaled on-disk datastructure that is not designed to support privacy, and privacy is not a feature you can add on top.
One option is to mount an encrypted disk image and put the cache in there. Similar to Mac OS X's FileVault for example. If you can figure out how to do that, you're golden.
Your other option is to implement your own cache, using the existing cache as a guide. Fair warning: the OkResponseCache is subject to change in the next release!
If I built an application that accessed some of the data from say Gmail, Twitter and Facebook, and I want the user to be able to only have to enter their authentication info once, and it's reset after some days or weeks, what is the best way to do this, dynamically, in Ruby?
I see a lot of people just having a config file of their clients'/users' credentials like so:
gmail_account:
username: myClient
password: myClientsPassword
This seems a) like it's very insecure, and b) it wouldn't work if I wanted to store this kind of information for thousands of users. What is the recommended way to do this?
I would like to be able to build an interface on top of these services, so having to enter credentials every time the user made a transaction isn't feasible.
If you're comforatable with the potential liability when a hacker gets into your database / filesystem, then go for it. And in all fairness, you should also disclose to your users that their passwords will be stored on your system, and let them decide if they want to give your program that level of trust.
But why do this in the first place? Facebook Connect and Twitter & Google using OAuth there's no need for you to store user passwords at all. At some point a user's cookies will expire (or they'll try to access your site from another computer) and they'll have to re-authenticate. You can't prevent re-authentication - instead, you should make it as easy for the end user to handle as possible.
Such services are providing OpenAuth authorization. You are strongly recommended to have a look at it.
Security
I assume your application needs to know the password in plaintext. Then there is no way around storing it in some kind of plain way.
Store in some kind of encoded way eg. Base64, this protects you from knowing password when looking through the database with your eyes, but it does not protect you from anything else.
Ensure that the files are not readable from any other user
Encrypt your harddrive, so nobody can get the passwords from stealing your harddrive. Your computer will require inputung you the password during booting.
Storing
There is nothing wrong with storing much data in your filesystem. For better performance you can do the following
One file for each user, so the filesystem and not ruby needs to search for the data
Make a lot of subdirectorys. Some filessystems performance suffer's if you put to many files into one directory. eg. put the file 'abcd' into 'a/b/c/d'
You could use a database instead of the filesystem
This is the way it works for instance for fetcmailrc which has to be chmod to 600 (readeable and writable only by his owner). And yes, it contains the plain password.
I would strongly suggest you to use OAuth, but if you have to store the passwords (please be absolutely sure that you need to do it) you could use the OpenSSL library to encrypt the passwords. The OpenSSL library is quite poorly documented in Ruby, but as far as I know they are quite similar to the C OpenSSL library. Since I think you should use OAuth, and not storing the passwords I'll let you find the documentation yourself.
However, for the OAuth approach, you want to take a look at the OAuth gem. Google, Twitter (which I recommend you to use the excellent twitter gem for) and facebook (which has two seemingly good alternatives: RFacebook and facebooker)
I was thinking of making a small tool. It is not important what the tool will do. The important thing, is that the tool will need to store some sensitive information on the user's HDD. EDIT: The information that will be stored is USER'S information - I'm not trying to protect my own content, that I distribute with the app.
I understand that I need to encrypt this information. But then, where do I safely store the encryption password? It's some sort of an infinite recursion...
So, is there a way, to encrypt information on windows, and have windows securely manage the passwords? When I say windows I mean Windows XP SP2 or later.
I should also note, that users on the same system must not have access to other users information (even when they are both running my application).
I'm looking for both - .NET 2.0 (C#) and native (C/C++) solutions to this problem.
is there a way, to encrypt information on windows, and have windows securely manage the passwords?
CryptProtectData: http://msdn.microsoft.com/en-us/library/windows/desktop/aa380261(v=vs.85).aspx
Using from .NET: http://msdn.microsoft.com/en-us/library/aa302402.aspx
Historically, Protected Storage (available in XP, read-only in vista+): http://msdn.microsoft.com/en-us/library/bb432403%28VS.85%29.aspx
You should consider using DPAPI for this purpose. It will encrypt your data with a special (internal) symmetric key which is on per-user basis. You don't even need to ask for passwords in this case, because different users on the system will have different keys assigned to them.
The downside of it might be that you can't recover the data if the user is deleted/Windows reinstalled (I believe that this is the case, not quite sure though). In that case encrypt the data with a "self-generated" key derived from the password and store the password in registry/file encrypted using DPAPI.
You can use the native encryption facility. Set the encrypt attribute on your folder or file (from the property page, click on the "advanced" button). Then you can set the users that can access the file (by default this only includes the file creator). The big advantage of this solution is that it is totally transparent from the application and the users points of view.
To do it programmatically: using the Win32 API, call EncryptFile() on the directory where you want to store your sensitive per-user data. From now on all newly created files within this dir will be encrypted and only readable by their creator (that would be the current user of your app). Alternatively you can use the FILE_ATTRIBUTE_ENCRYPTED flag on individual files at creation time. You can check encryption info from the explorer on the file's property page, and see that app-created files are correctly encrypted and restricted to their respective users. There is no password to store or use, everything is transparent.
If you want to hide data from all users then you can create a special app-specific user and impersonate it from your app. This, along with ACLs, is the blessed technique on Windows for system services.
You might want to look at Isolated Storage, which is a way of storing settings and other data on a per-application data automatically.
See an example and MSDN.
This is an alternative to storing normal settings in the registry, a better one in a lot of cases... I'm not sure how the data is stored to file however so you'd need to check, you wouldn't want it to be accessible, even encrypted, to other users. From memory only the app. that created the storage can open it - but that needs checking.
Edit:
From memory when I last used this, a good approach is to write a "Setting" class which handles all the settings etc. in your app. This class then has the equivalent of Serialize and DeSerialize methods which allow it to write all its data to an IsolatedStorage file, or load them back again.
The extra advantage of implementing it in this way is you can use attributes to mark up bits of the source and can then use a Property Grid to quickly give you user-edit control of settings (the Property Grid manipulates class properties at runtime using reflection).
I recommend you look at the Enterprise Library Cryptography Application Block. Check this blog post. Windows has a built in Data Protection API for encrypting data, but the Crypto Application Block makes it more straightforward.
Um, what you're trying to achieve is exactly what DRM tried to achieve. Encrypt something then give the user the keys (however obfuscated) and the crypto. They did it with DVDs. They did it with Blu-Ray. They did it with iTunes.
What you are proposing to do will never be secure. Your average lay person will probably not figure it out, but any sufficiently motivated attacker will work it out and discover the keys, the algorithm and decrypt the data.
If all you're doing is encrypting user data then ask the user for their password. If you're trying to protect your internal data from the user running the application you're S.O.L.
Erm hash the password? You don't need to store the real deal anywhere on the machine just a hashed password (possibly salted too). Then when the user enters their password you perform the same operation on that and compare it to the hashed one you've stored on disk.
Is it possible to store passwords on the local system (Windows XP) that can only be accessed by the application itself?
My instinctive answer would be "no". Even if some kind of hashing or encyption is used I would think that as long as the source code is available then the determined seeker could always use this to retrieve the password.
I'm working on a personal open source hobby project in which I would like to give users the option of storing passwords on disk so that they don't need to type them every time they use the software. One example of a password that could be stored would be the one used to authenticate on their network's proxy server.
There are a few related questions here on Stack Overflow and the most appropriate solution sounds like using an operating system service like DPAPI.
Is the basic premise correct that as long as the password is retrievable by the software without any user input, and the source code is open source, that the password will always be retrievable by a (suitably technically and willfully inclined) passer-by?
You could read about the Pidgin developers' take on it here:Plain Text Passwords.
Using the DPAPI in UserData mode will only allow your account on your machine to access the encrypted data.
It generates a master key based off of your login credentials and uses that for the encryption.
If the password is retrievable by the software without any user input, then the password will always be retrievable by a (suitably technically and willfully inclined) passer-by. Open or closed source only affects how much effort is involved.
Absolutely, you can write a program to store passwords securely.
Using AES, you could have your program generate an AES Key, and have that key stored in an operating system protected area. In WinXP, this is the registry, encrypted with DPAPI. Thus the only way to access the key is to have physical access to the machine.
You need to ensure that when you generate your AES key that you do so in a cryptographically secure manner. Just using RAND won't work, nor will generating a random character string.
Open Source has very little to do with security (in my opinion). Given the level of sophistication in tools for reverse engineering source code, even if you had a closed source solution, people determined to snoop at your code could do so.
Your effort is better spent ensuring that you follow best practice guidelines while using the chosen encryption scheme. I would argue that having your code openly looked at by a larger community would actually make your code more secure; vulnerabilities and threats would likely be identified sooner with a larger audience looking through your code.