Re: Entropy Pool Contents

Phillip Susi
2006-11-27T20:38:09Z

David Wagner wrote:
> Nope, I don't think so. If they could, that would be a security hole,
> but /dev/{,u}random was designed to try to make this impossible, assuming
> the cryptographic algorithms are secure.
>
> After all, some of the entropy sources come from untrusted sources and
> could be manipulated by an external adversary who doesn't have any
> account on your machine (root or non-root), so the scheme has to be
> secure against introduction of maliciously chosen samples in any event.

Assuming it works because it would be a bug if it didn't is a logical
fallacy. Either the new entropy pool is guaranteed to be improved by
injecting data or it isn't. If it is, then only root should be allowed
to inject data. If it isn't, then the entropy estimate should increase
when the pool is stirred.