[RFC v2 00/13] Multi-Key Total Memory Encryption API (MKTME)

[Sakkinen, Jarkko]

On Fri, 2018-12-07 at 14:57 +0300, Kirill A. Shutemov wrote:
> > What is the threat model anyway for AMD and Intel technologies?
> > 
> > For me it looks like that you can read, write and even replay 
> > encrypted pages both in SME and TME. 
> 
> What replay attack are you talking about? MKTME uses AES-XTS with physical
> address tweak. So the data is tied to the place in physical address space and
> replacing one encrypted page with another encrypted page from different
> address will produce garbage on decryption.

Just trying to understand how this works.

So you use physical address like a nonce/version for the page and
thus prevent replay? Was not aware of this.

/Jarkko