Computing with traps • Hacker News Board

Re: Computing with traps

#11

Post by jbangert » Mon, Jun 29, 2015, 9:09 PM UTC

Author here. The point of this work is not only the specific result (lots of VM edge cases, very hard to reverse engineer source of computation), but to promote this general class of 'problem' -- things that are typically not thought to be so complicated actually containing a Turing-complete executionenvironment. Other examples include ELF and DWARF binary files, PDF, etc. etc.

Once you need to evaluate a Turing machine to see what a file (or in my case, a set of page tables) actually means, you loose a lot of tractability.

Re: Computing with traps

#12

Post by [deleted] » Tue, Jun 30, 2015, 1:16 AM UTC

amelius wrote: post #8

duaneb wrote: post #7

Earlier quoted context omitted.

All security is through solutions being obscure. I don't understand this criticism. Encryption just puts mathematical bounds on the obscurity, for instance, and a lock only works through the obscurity of having to find a crowbar. Security is measured through degrees and layers. No secure system is provably secure to all attacks. Something like the above would definitely add a lot to the cost of attempting to understa…

> All security is through solutions being obscure. I don't understand this criticism. Encryption just puts mathematical bounds on the obscurity There is a difference. Once somebody writes a tool to unravel the obscurity, it is simple and fast for everybody to break the security. Not so with encryption (if used properly, with changing keys, one-time passwords, etc.)

[deleted]

Re: Computing with traps

#13

Post by duaneb » Tue, Jun 30, 2015, 3:33 PM UTC

amelius wrote: post #8

duaneb wrote: post #7

Earlier quoted context omitted.

All security is through solutions being obscure. I don't understand this criticism. Encryption just puts mathematical bounds on the obscurity, for instance, and a lock only works through the obscurity of having to find a crowbar. Security is measured through degrees and layers. No secure system is provably secure to all attacks. Something like the above would definitely add a lot to the cost of attempting to understa…

> All security is through solutions being obscure. I don't understand this criticism. Encryption just puts mathematical bounds on the obscurity There is a difference. Once somebody writes a tool to unravel the obscurity, it is simple and fast for everybody to break the security. Not so with encryption (if used properly, with changing keys, one-time passwords, etc.)

> Once somebody writes a tool to unravel the obscurity, it is simple and fast for everybody to break the security.

Yes, it has a lower bound. But that tool has a high obscurity level itself. So the lower bound on breaking the security is finding someone who can write that tool.

Not great, but decent to buy time, as I said before :)