Scott McGuire wrote:
Cerridwyn Llewyellyn wrote:
I need an algorithm/protocol that is capable of encrypting numerous files with separate keys, but there also needs to be a master key that will be able to decrypt all of them. Is there such a system that is relatively secure? I'd prefer the system to be as secure as possible, but in this application, security is secondary to functionality. Thanks... //cerridwyn//
Are you after a working program, or just a design?
You could always use an escrowed public key generator (discussed on sci.crypt some time ago), where the keys all have a factor of 'N' embedded in 'N', but encrypted with the master key.
(I'd be prepared to write the code that generates the keys, if someone does the "master decrypt" side of things).
Why not just encrypt the files with regular, single key encryption and only use the public-key encryption on a master file holding a copy of all the individual keys? This would be faster right?
The main reason is so that anyone can generate new keys as and when they please. The master key is not required for key generation, which makes it more secure (ie. it spends more of its time in the safe) and practical (the master key may be in a different building). Gary -- pub 1024/C001D00D 1996/01/22 Gary Howland <gary@systemics.com> Key fingerprint = 0C FB 60 61 4D 3B 24 7D 1C 89 1D BE 1F EE 09 06 ^S ^A^Aoft FAT filesytem is extremely robust, ^Mrarely suffering from^T^T