Re: RDB-based secure data storage

["Calum Power" <enune () fribble net>]

Excellent! That's Ivan, that's just the sort of thing I was looking for.

Got any idea if there's any libraries/implementations that I might be able
to use to get my head around implementing it myself?

Thanks again!

Cheers,

Calum


> Calum Power wrote:
> > G'day webappsec,
> >
> > I have been asked by my employer to design a system for storing
> > sensative
> > private data collected from the company's clients. They tell me that
> > this
> > data MUST be very secure, yet clients must be able to update the
> > information themselves via a Web-based interface.
> >
> > My immediate reaction was to use something like GPG/PGP to encrypt the
> > data before storing it in a RDBMS like MySQL. However this then has the
> > additional problem of needing the user to edit the data.
> >
> > My next thought would be to have each clients 'username' be a public GPG
> > key, and their 'password' be the passphrase to this private key. This of
> > course would not be overly secure, and the 'administrator' of this would
> > not be able to update the information without using the users' password.
> >
> > So, I was just wondering if anyone had come across the same problem.
> > Perhaps there's a method of encryption that I'm overlooking.
>
>    You can combine encryption methods to achieve the goal:
>
>    1. Generate a private-public key pair for every user.
>
>    2. For each piece of information you store, generate a new secret and
>       use it to encrypt information (using symmetrical encryption for
>       better performance).
>
>    3. Never store the secret in plain text. Instead, create a copy of
>       the secret for every user that has the right to access the
>       information, and store the secret encrypting it with their
>       public key. When a user want to access a piece of information,
>       their private key will be used to decrypt the secret, and then
>       the secret will be used to decrypt the actual data.
>
>    4. It would be a good idea to have a special public-private
>       key pair, to use it to encrypt all secrets that are generated,
>       for backup purposes.
>
> --
> ModSecurity (http://www.modsecurity.org)
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