ABAP Secure Storage: how to store passwords? - security

I never needed to store passwords in an ABAP System.. now it's time to learn something new...
I need to store a password, which I use on an ABAP System to connect to a different system, so I cant store a (oneway) hash.
I came across some function modules like FIEB_PASSWORD_ENCRYPT (which is using a hardcoded key) or some suggestions of storing a base64 encoded version of the password (gosh!) => both would only prevent anyone from "quickly reading" the password if it is on the screen, not prevent anyone from stealing it.
I also came across SECSTORE (SAP Help Link), which apparently is only usable by SAP components not by custom applications.
Basically, my need is
store password in some DB table in encrypted form
impossible (at least very hard) to get the pw by plain select on that table
get from the DB table in clear form to be able to pass it to the "other system"
I don't want to re-invent the wheel, especially not in a security area.
I think, there MUST be something there that can be used for that purpose...
UPDATE Why do I need that:
I'm accessing an HTTPS System (destination type G) and all connection params are configured in the destination.
unfortunately, a PW needs to be transmitted in body as form parameter
Disclaimer: I am in discussion currently whether this can be turned into basic auth, which is neither more nor less secure (header vs. body). But with basic auth, I can use the destination config, which in turn uses SECSTORE. This discussion is a long story as many parties are involved and the access to the system is multi-layered...

You can use SSF_KRN_ENVELOPE function for encrypt and SSF_KRN_DEVELOPE for decrypt. It use RSA standart so result may be huge. I prefer use ABAP AES class at https://github.com/Sumu-Ning/AES
These functions using system certificates, AES library needs IV and keys so if user has debug or developer authorization he can get get it.
Correct way is using standard ways for communication. For example using SOAP client with basic authentication and save password in SOA manager. Also basic authentication can be used http and https protocols in SM59 configuration.

The option I post here is an option without encryption, but seems "quite secure (tm)". Feel free to comment
store the password in a DB table as plain text
set that table as "N : display/modification not allowed"
create a program for writing the PW into that table
there is no probram that will output the PW.
This means that, in a productive ABAP environment, only someone with at least one of the following permissions can access the PW (correct me if I am wrong)
Debugging permissiosn on production (basically no-one)
direct DB access (basically no-one)

Related

How should I store a known/hard-coded password in the database?

I have a web app that uses known username and password combinations to login to external servers. There are multiple username/password combinations used for different services. Right now, they are essentially "hard-coded" into the website code, but, I would like to move this information off the code base for better security.
My initial thought is to store this data in the database which is used to support the website. I want to store it in a way that it is not easily "hackable" (i.e. I'm not going to store it as plain text or as a MD5 hash). Should I follow the same format that I use to store the website user's passwords, where I use a random number generator to create SALT for each password and then store the password as hashed combination of the password and SALT, or would this be overkill?
Generally, storing passwords in the application code is always a bad idea. Moving it outside the code has many advantages including security.
Now storing it either in DB or Configuration Files is a choice you have to take depending on your application.
For full security you should never store passwords in retrievable form. But to login to a external server as in your case, you need to get the actual plain text password, so one way hash will not work for you.
In our product we deal with such situation by using 2 Way SSL Certificates. It is very secure and there is no need to store the passwords.
But if you really need to store the passwords, then I will suggest to use configuration file and let your application read it. You can encrypt the passwords stored in the configuration files (Encrypting the passwords stored in the configuration file will again bring you back to the same question of how to protect the key). The access to the configuration file should be restricted (in Unix, 600 File Permission).
Alternatively, if your web application is Java, then you can consider using JNDI.
After more research, I've decided at this point to follow the ideas here:
Encrypt a Column of Data - SQL Server | Microsoft Docs
...and encrypt/decrypt on the DB inside a Stored Procedure.

Need suggestions on how to create a website with an encrypted database

I want to create a website where a user enters content (say a couple of sentences) which eventually gets stored in a backend database (maybe MySQL). But before the content leaves the client side, I want it to get encrypted using something on client like maybe javascript.
The data will travel over the web encrypted, but more importantly, will also be permanently stored in the backend database encrypted.
Is JavaScript appropriate to use for this? Would 256 bit encryption take too long?
Also, how do you query an encrypted database later on if you want to pull down the content that a user may have submitted over the past 2 months?
I'm looking for tips, suggestions and any pointers you guys may have in how to go about learning about and accomplishing this.
Thanks!
You shouldn't implement the encryption for the communication between the client and the server yourself, use SSL (https) for that. As for encrypting data in the database, you can always use MySQL's built-in methods, such as AES_ENCRYPT and AES_DECRYPT, see reference manual for details.
Look at http://www.farfarfar.com/scripts/encrypt/ (encrypt/decrypt).
Tried text/text/XXTEA with success.
However, that's about as far you can go with JS encryption.
As long as you're not using SSL/https, the main disadvantage is:
A fuzz to protect the private key, (it can be done though, like a form field, not submitted, but requires user to enter value on each session.)
About searching/extracting data on encypted data, I belive nothing is going to work.
Well, to point out something: if it's client side encrypted, it'll likely also be easily decrypted, seeing as with languages like javascript, they're being handed the source code of your encryption scheme. Plenty of encryption schemes out there, AES, Blowfish, etc, but if the data is traveling on an encrypted connection, I suppose the encryption of the data only adds very little security, maybe packet sniffers locally installed or something to that effect.
I would also suggestion you look into using compression as well, I myself have used LZMA, Huffman, and even base64 encoding with javascript to at least obscure the content from casual observers. Point being, no matter how good the encryption, you're handing over the process to the client, and they can just view your source and be able to easily reverse the encryption, given that they know the encryption scheme and aren't to lazy to do a bit of Googling or searching on Wikipedia. I personally prefer compression because it also reduces the size of the data being sent, and unless one is trained in analysis of encryption and compression, it is isn't easy to figure out the compression being used from sniffing packets.
EDIT: But if you want high levels of security, I would suggest against using just compression, and instead, using an asymmetric encryption method like RSA or Diffie-Hellman encryption on data traveling between the server and client, as the private key will never be shared.
For client side, javascript or better, a Java application, would work (at least you can't right click -> view source with a Java app in two seconds). 256 bit encryption wouldn't take too long if you're just wanting to save a few sentences like you said. A modern processor with blast through that in milliseconds. Then, when it arrives at the server, encrypt it using AES or another powerful algorithm (note that the US government uses AES 256 for their Top Secret documents) before sending it to the database. (Also want to add that you can also store a hash (MD5 is a function readily available in PHP, you can opt for something like Whirlpool as well, but you'll have to find a library for that) of the data on a separate database, and check against it when you access it to ensure that your database hasn't been compromised)
For querying, I suggest PHP. Read the data, decrypt it, then send to the client (in still encrypted form), or if you want, and have the client decrypt it also, if you don't trust the networks the data is being sent through.
Here's a good source on Javascript and AES: http://point-at-infinity.org/jsaes/
My two saved links using RSA in javascript: http://www.ohdave.com/rsa/ and http://www.hanewin.net/encrypt/rsa/rsa.htm
As for the data being sent over the network encrypted, this is the kind of thing that HTTPS was made for. Nothing is transmitted in the clear. It's encrypted securely enough for most banks to trust it. Don't reinvent the wheel here; it'll never be as round as what a bunch of people who make wheels for a living have come up with.
Have your form submit to an https:// url (rather than http://), and the script/app at that URL talk to the database, encrypting and decrypting the data as needed. Javascript won't easily talk directly to MySQL anyway, and if you do all the encryption client-side, anyone who can get the page can still decrypt it (since by necessity the client would need to be given the decryption key as well).
Check out this blogpost: http://www.ravellosystems.com/blog/all-you-need-to-know-to-configure-ssl-offloading/
It takes you through all the steps you need to do to configure your webs server to serve content under an encrypted channel (a.k.a SSL termination).

How can you encrypt users' data server-side without ruining the experience?

Many users – myself included – would like the security of having everything they do on a web service encrypted. That is, they don't won't any one at the web service to be able to look at their: posts, info, tasks, etc...
This is also major complaint in this discussion of an otherwise cool service: http://news.ycombinator.com/item?id=1549115
Since this data needs to be recoverable, some sort of two-way encryption is required. But unless you're prompting the user for the encryption key on every request, this key will need to be stored on the server, and the point of encrypting the data is basically lost.
What is a way to securely encrypt user data without degrading the user experience (asking for some key on every request)?
-- UPDATE --
From #Borealid's answer, I've focused on two possibilities: challenge-response protocols, where no data (password included) is sent in the "clear", and non-challenge-response protocols, where data (password included) is sent in the "clear" (although over HTTPS).
Challenge-response protocols (specifically SRP: http://srp.stanford.edu/)
It seems that its implementation would need to rely on either a fully AJAX site or using web storage. This is so the browser can persist the challenge-response data during encryption and also the encryption key between different "pages". (I'm assuming after authentication is completed I would send them back the encrypted encryption key, which they would decrypt client-side to obtain the real encryption key.)
The problem is that I'm either:
fully AJAX, which I don't like because I love urls and don't won't a user to live exclusively on a single url, or
I have to store data encryption keys in web storage, which based on http://dev.w3.org/html5/webstorage/ will persist even after the browser is closed and could be a security vulnerability
In addition, as SRP takes more than one request ( http://srp.stanford.edu/design.html ), there needs to be some persistence on the server-side. This is just another difficulty.
Traditionally
If I'm ok transmitting passwords and data in the clear (although over HTTPS), then the client-side issues above are not present.
On registration, I'll generate a random unique encryption key for the user, and encrypt it using their password and a random salt.
In the database, I'll store the user's password hash and salt (through bcrypt), encrypted encryption key, encryption key salt, and encryption iv.
After an authentication, I'll also need to use their password to decrypt the encryption key so that they may view and enter new data. I store this encryption key only temporarily and delete it when they explicitly "log out".
The problems with this approach is that (like #Borealid points out) evil sysadmins can still look at your data when you are logged in.
I'm also not sure how to store the encryption keys when users are logged in. If they are in the same data store, a stolen database would reveal all data of those who were logged in at the time of theft.
Is there a better in-memory data store for storing these encryption keys (and challenge data during an SRP authentication)? Is this something Redis would be good for?
If the data need to be recoverable in the event of user error, you can't use something like a cookie (which could get deleted). And as you point out, server-side keys don't actually secure the user against malicious sysadmins; they only help with things like databases stolen offline.
However, if you're running a normal web service, you've already gotten pretty lucky - the user, in order to be unique and non-ephemeral, must be logged in. This means they go through some authentication step which proves their identity. In order to prove their identity, most web sites use a passed credential (a password).
So long as you don't use a challenge-response authentication protocol, which most web sites don't, you can use an encryption key derived from a combination of a server-side secret and the user's password. Store the encryption key only while the user is authenticated.
If you do this, the users are still vulnerable to sysadmins peeking while they're using the service (or stealing their passwords). You might want to go a step further. To go one up, don't send the password to the server at all. Instead, use a challenge-response protocol for authentication to your website, and encrypt the data with a derivative of the user's password via JavaScript before uploading anything.
This is foolproof security: if you try to steal the user's password, the user can see what you're doing because the code for the theft is right there in the page you sent them. Your web service never touches their data unencrypted. This is also no hindrance to the normal user experience. The user just enters their password to log in, as per normal.
This method is what is used by Lacie's storage cloud service. It's very well done.
Note: when I say "use foo to encrypt", I really mean "use foo to encrypt a secure symmetric key which is then used with a random salt to encrypt". Know your cryptography. I'm only talking about the secret, not the methodology.
None of those other solutions are going to maintain the feature set requested -- which specifically wants to preserve the user experience. If you look at the site referenced in the link, they email you a nightly past journal entry. You're not going to get that with JavaScript trickery per above because you don't have the browser to depend on. So basically this is all leading you down a path to a degraded user experience.
What you would want, or more precisely the best solution you're going to find in this space, is not so much what wuala does per above, but rather something like hush.com. The handling of user data needs to be done on the client side at all times -- this is generally accomplished via full client-side Java (like the Facebook photo uploader, etc), but HTML/JavaScript might get you there these days. JavaScript encryption is pretty poor, so you may be better off ignoring it.
OK, so now you've got client-side Java running a Journal entry encryption service. The next feature was to email past journal entries to users every night. Well, you're not going to get that in an unencrypted email obviously. This is where you're going to need to change the user experience one way or the other. The simplest solution is not to email the entry and instead to provide for instance a journal entry browser in the Java app that reminds them of some old entry once they get to the website based on a link in the daily email. A much more complex solution would be to use JavaScript encryption to decrypt the entry as an attachment inline in the email. This isn't rocket science but there is a fairly huge amount of trickery involved. This is the general path used by several web email encryption services such as IronPort. You can get a demo email by going to http://www.ironport.com/securedemo/.
As much as I'd love to see a properly encrypted version of all this, my final comment would be that journal entries are not state secrets. Given a solid privacy policy and good site security semantics, I'm sure 99% of your users will feel just fine about things. Doing all this right with true security will take an enormous amount of effort per above and at least some design/UE changes.
You should look into the MIT project CryptDB which supports querying an encrypted database using a subset of SQL. (see the forbes article, mefi thread, or Homomorphic encryption on wikipedia)
There is the Tahoe-LAFS project for cloud storage too, which conceivably could be leveraged into a fully anonymous social networking application, one day in the distant future.
If you want to perform computations on a server without even the server being able to see the data, you may be interested in knowing about fully homomorphic encryption. A fully homomorphic encryption scheme lets you perform arbitrary computations on encrypted data, even if you can't decrypt it. However, this is still a topic of research.
For now, I guess your best bet would be to encrypt all posts and assign meaningless (e.g. sequential) IDs to each one. For a more in-depth discussion of how to encrypt server-side data with today's technology, look up.

How to verify an application is the application it says it is?

Here's the situation: we have a common library which can retrieve database connection details from a central configuration store that we have setup. Each application uses this library when working with a database.
Basically, it will call a stored procedure and say "I am {xyz} application, I need to connect o " and it will return the connection details for that applications primary database (server, instance, database, user, and password).
How would one go about locking that down so that only application {xyz} can retrieve the passwords for {xyz} databases (there is a list of database details for each application... i just need to secure the passwords)?
The usual way is to have a different config store per app and give each app a different user/password to connect to the config store.
That doesn't prevent anyone from changing the app and replacing the user/password for app X with the values from app Y but it's a bit more secure, especially when you compile this data in instead of supplying it via a config file.
If you want to be really secure, you must first create a secure connection to the store (so you need a DB drivers that supports this). This connection must be created using a secure key that is unique per application and which can be verified (so no one can just copy them around). You will need to secure the executable with hashes (the app will calculate its own hash somehow and send that to the server who will have a list of valid hashes for each app).
All in all, it's not something trivial which you can just turn on with an obscure option. You will need to learn a lot about security and secure data exchange, first. You'll need a way to safely install your app in an insecure place, verify its integrity, protect the code against debuggers that can be attached at runtime and against it running in the virtual machine, etc.
Off the top of my head, try PKI.
Are you trying to protected yourself from malicous programs, and is this a central database that these applications are connecting to? If so you should probably consider a middle layer between your database and application.
I'm not sure this applies to your case, depending on how what your answers to the abovementioned would be, but by the comments it sounds like you are having a similar case to what this question is about.
Securing your Data Layer in a C# Application
The simplest/most straightforward way would be to store the passwords in encrypted format (storing passwords in plaintext is just plain bad anyhow, as recently demonstrated over at PerlMonks) and make each application responsible for doing its own password encryption/decryption. It would then not matter whether an app retrieved another app's passwords, as it would still be unable to decrypt them.
One possibility is to keep the passwords in the database in an encrypted form, and convey the encryption key to the allowed application(s) in a secure connection.Then, only the application with the encryption key can actually get the passwords and not others.

Encrypting 3rd party credentials

I have an application where I need to store 3rd party credentials to services like Amazon S3, FTP, SFTP, etc..
I know that it is possible to access some of those systems without passwords, but that has its own issues. If our customers gave us access to their S3 buckets via ACL we would still need to verify which bucket belongs to which user, same goes for SFTP and ssh key auth.
We will try our best to allow non-password alternatives where possible, but sometimes (FTP) it just won't be possible. Therefor I am looking for advice on how to store this sensitive data in our database (MySql) or elsewhere.
In the past I have read about people using TrueCrypt partitions that automatically unmount, but that would probably require decent intrusion detection. For now I'm interested in simple approaches that lead to reasonable security and can improved upon in the future.
Any advice on the subject would be highly appriciated!
There are a range variety of possibilities and since in my opinion you provide not enough info about the context, i will try to give you an overview from my point of view. I assume that here the most important aspect is confidentiality of your data and and authentication of the users. Integrity and availability of data is much less important.
If you want basic security, you can let MySQL handle it by means of username/password combinations and set access rights on the given account. However, since the access control mechanism of mysql is not fine-grained (you can set access control rules per table only, not per row) this will probably yield a bad database design.
If you want to have a non-password approach, you can give users client-certificates and let them prove their identity by presenting their client certificates (use TLS for that) or let them sign something (note their are dangers because you create a so called signing oracle).
Another approach is to encrypt your data in the database. You can do that by deriving a symmetric key from the password and encrypt the credentials with this data. The catch here is of course that your key derivation protocol should be good and this is not easy to accomplish (so if you choose this, i advice you to take existing key derivation protocols or use a streamcipher). Take a look here for a list of streamcipher http://en.wikipedia.org/wiki/Stream_cipher .
If you care very much for security you can start thinking about fancy solutions like authentication with smartcards, or a time synchronized tamper resistant device for generating acccess codes. However, note that these fancy solutions do not give you free security, implementing such systems if hard and costly (due to development and deployment) however, if done correctly they provide the best security.
Have the user supply a (strong) password when they set up an account (before they provide their passwords). Then encrypt all data for that account within your database using a key derived from a strong hash (SHA256 or something like that) of the user's password. That way if your servers get compromised, no data will be revealed because it is encrypted with the user's password (well, a hash of the user's password) and that password is not stored anywhere on your server.
You need to investigate the use of keystores. TruCrypt is an example of such a keystore, but this is a personal keystore, not intended for service level credentials.
You won't be able to avoid storing their passwords in a format that someone can get access to, the goal is to minimize who can access the information. Putting in the same MySQL as application data is asking for disaster.

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