On Thu, Sep 21, 2017 at 11:16 AM, Philip Hands <[email protected]> wrote:
> Most of the time, what you're calling hardware is liable to just be > software running on a different processor, perhaps in a box that has > been glued shut such that it's less convenient for bugs to be found, > fixed and patched. glued shut, electric fences added which electrocute the user, or run the instruction "HCF" [Halt and Catch Fire. mythical iinstruction which was supposed to be in the 68000 or perhaps the 8086, but was actually down to running a loop of instructions that flipped IO and internal logic so hard that the processor overheated). :) the latest freescale has an on-board Cortex M0 i think it is, which is ultra-low-power enough to run permanently on battery, so you can do tamper-detection. you'll like this: when i was working for NC3A i was asked to help with a little ethernet network box that transferred data from a low-security environment to a high-security one. the rule was simple: absolutely no physical connection, and absolutely no data must travel - ever from the high security level to the low security one. that *includes* ICMP packet responses which are normally used to acknowledge and set up even a *UDP* connection. so somebody wrote a *modified* TCP stack which took out the need for ICMP traffic... but it went way waaay further than that. the metal box was implemented as an ultra-low power receiver / transmitter pair, with a metal firebreak and a tiny hole between for the radio signal to get through on a Coax cable (so that there was no data leakage by emitted radio waves). power was SEPARATELY provided on both sides of the box. then.... when it was confirmed 100% working, the ENTIRE BOX WAS FLOODED WITH RESIN. bit of a heat problem, that.... baiscally what i'm saying, with this story is: the tricky part will not be the software at all: the tricky bit will be getting a processor into a tamper-resistant, tamper-detecting box. l. _______________________________________________ arm-netbook mailing list [email protected] http://lists.phcomp.co.uk/mailman/listinfo/arm-netbook Send large attachments to [email protected]
