Security - Best Encryption Mechanism

[gaurav khanna]

Hi

I need to store the credit card information in my database. I have
been looking for some third party tools which could provide encryption
for credit card numbers.

The help I need is:

a) What is the most secure encryption tool that can be used to store
credit card information?

b) Any tool which implements AES and does not expect a private key to
be supplied as shown in the sample application provided by
Microsoft. But in this case customize tool needs to be provided as
anybody can buy the tool and decrypt the information.

c) What is the best way to secure a private key used by the
algorithm like storing in RAM, registry, isolated storage etc? And
how to implement it.

d) If some code implementation, which allows encrypting securely
is available.


The client is ready to invest in Third Party Tool.
I short listed two third party .Net components for encryption:

Chilkat Software (http://www.chilkatsoft.com/dotNetCrypt.asp)

ezCrypto .NET (http://www.componentsource.com/Cata...S&PO=514745&option=10444&RC=FCSR&POS=1&bhcp=1
)


Both the above are c# implemented tools and implement AES algorithm.

But the problem is both ask for private key to be supplied. And I need
to store the private key in a secure manner.


The work round I decided was to use the dll provided by the tool.
Write some login to generate dynamically private key for each of the
registered users based on his profile. Store this logic in a dll and
some how secure this logic, so that no body is able to access it. But
how to secure the logic is a concern, as dll can also be hacked to
view its contents.

One option I was looking at was to use isolated storage as provided by
..Net.
But I'm not sure can we store and access a dll using isolated storage.


It would be great if somebody can help me with the above problem.

Regards
Gaurav

 

[Nick Holmes]

If you need to store a key in your code, then you should look at DPAPI.
There is not standard .Net implementation of it (its a Win32 API), but all
you need to know is here:
http://msdn.microsoft.com/library/default.asp?url=/library/en-us/secmod/html/secmod21.asp

Nick Holmes.

 

[Daniel Billingsley]

With code so easily reverse-engineered, isn't that considered a giant
security hole itself?