Re: summary Re: encrypted swap

[David Wagner]

Ben Ford  wrote:
>David Wagner wrote:
>>You missed some scenarios.  Suppose I run a server that uses crypto.
>>If swap is unencrypted, all the session keys for the past year might
>>be laying around on swap.  If swap is encrypted, only the session keys
>>since the last boot are accessible, at most.  Therefore, using encrypted
>>swap clearly reduces the impact of a compromise of your machine (whether
>>through theft or through penetration).  This is a good property.
>
>Wiping swap on boot will achieve the same effect.

No, it won't.  Or rather: Yes, it would, if you could erase data
reliably, but it's not clear that you can.  Once again, please see
Peter Gutmann's paper on the difficulty of erasing data reliably.