Re: [PATCH] CPU Jitter RNG: inclusion into kernel crypto API and /dev/random

2013-11-06 Thread Stephan Mueller
Am Dienstag, 5. November 2013, 14:45:58 schrieb Stephan Mueller: Hi Pavel, >Am Dienstag, 5. November 2013, 13:25:40 schrieb Stephan Mueller: > >Hi Pavel, > >>Am Montag, 4. November 2013, 00:32:07 schrieb Pavel Machek: >>>But they usually _do_ have RTC or other clock, not driven by CPU >>>oscilato

Re: [PATCH] CPU Jitter RNG: inclusion into kernel crypto API and /dev/random

2013-11-06 Thread Stephan Mueller
Am Dienstag, 5. November 2013, 13:20:57 schrieb Stephan Mueller: Hi Ted, >Am Sonntag, 3. November 2013, 07:41:35 schrieb Theodore Ts'o: > >Hi Theodore, > >>On Sun, Nov 03, 2013 at 08:20:34AM +0100, Stephan Mueller wrote: >> >>Sandy Harris pointed out a very good paper that I would definitely >>re

Re: [PATCH] CPU Jitter RNG: inclusion into kernel crypto API and /dev/random

2013-11-06 Thread Theodore Ts'o
On Wed, Nov 06, 2013 at 12:49:45PM +0100, Stephan Mueller wrote: > Here is a quote from his answer to my question whether he was able to > identify the root cause: > > "its inherent in the microtiming of Hardware and there is nothing you > can do about it if you want the root cause is quantum ph

Re: [PATCH] CPU Jitter RNG: inclusion into kernel crypto API and /dev/random

2013-11-06 Thread Stephan Mueller
Am Mittwoch, 6. November 2013, 07:43:54 schrieb Theodore Ts'o: Hi Theodore, >On Wed, Nov 06, 2013 at 12:49:45PM +0100, Stephan Mueller wrote: >> Here is a quote from his answer to my question whether he was able to >> identify the root cause: >> >> "its inherent in the microtiming of Hardware an

Re: [PATCH] CPU Jitter RNG: inclusion into kernel crypto API and /dev/random

2013-11-06 Thread Theodore Ts'o
On Wed, Nov 06, 2013 at 01:51:17PM +0100, Stephan Mueller wrote: > >That's unfortunate, since it leaves open the question of whether this > >jitter is something that could be at least somewhat predictable if you > >had a lot more information about the internal works of the CPU or > >not > > I

Re: [PATCH] CPU Jitter RNG: inclusion into kernel crypto API and /dev/random

2013-11-06 Thread Pavel Machek
Hi! > Of course, some of the state in the CPU may not be unknown to the > attacker, if it is derived by external events that are not visible to > the attacker, such as a network interrupt. But if that's the case, > why not measure network interrupts directly? We're much less likely > to overesti

Re: [PATCH] CPU Jitter RNG: inclusion into kernel crypto API and /dev/random

2013-11-06 Thread Pavel Machek
Hi! > >I plugged that idea into my current Jitter RNG processing and disabled > >the other jitter measurements to get a clear, isolated picture. > > > >The result is also a white noise! And it is even quite fast. > > After doing some more research on this approach, I have to admit that > the out

Re: [PATCH] CPU Jitter RNG: inclusion into kernel crypto API and /dev/random

2013-11-06 Thread Nicholas Mc Guire
On Wed, 06 Nov 2013, Pavel Machek wrote: > Hi! > > > Of course, some of the state in the CPU may not be unknown to the > > attacker, if it is derived by external events that are not visible to > > the attacker, such as a network interrupt. But if that's the case, > > why not measure network inte

Re: [PATCH] CPU Jitter RNG: inclusion into kernel crypto API and /dev/random

2013-11-06 Thread Nicholas Mc Guire
On Wed, 06 Nov 2013, Stephan Mueller wrote: > Am Mittwoch, 6. November 2013, 07:43:54 schrieb Theodore Ts'o: > > Hi Theodore, > > >On Wed, Nov 06, 2013 at 12:49:45PM +0100, Stephan Mueller wrote: > >> Here is a quote from his answer to my question whether he was able to > >> identify the root ca

Re: [PATCH] CPU Jitter RNG: inclusion into kernel crypto API and /dev/random

2013-11-06 Thread Stephan Mueller
Am Mittwoch, 6. November 2013, 14:26:35 schrieb Pavel Machek: Hi Pavel, >Hi! > >> >I plugged that idea into my current Jitter RNG processing and >> >disabled >> >the other jitter measurements to get a clear, isolated picture. >> > >> >The result is also a white noise! And it is even quite fast. >

Re: [PATCH] CPU Jitter RNG: inclusion into kernel crypto API and /dev/random

2013-11-06 Thread Stephan Mueller
Am Mittwoch, 6. November 2013, 08:04:32 schrieb Theodore Ts'o: Hi Theodore, >On Wed, Nov 06, 2013 at 01:51:17PM +0100, Stephan Mueller wrote: >> >That's unfortunate, since it leaves open the question of whether >> >this >> >jitter is something that could be at least somewhat predictable if >> >yo

Re: [PATCH] CPU Jitter RNG: inclusion into kernel crypto API and /dev/random

2013-11-06 Thread Stephan Mueller
Am Donnerstag, 7. November 2013, 02:03:57 schrieb Nicholas Mc Guire: Hi Nicholas, >On Wed, 06 Nov 2013, Stephan Mueller wrote: >> Am Mittwoch, 6. November 2013, 07:43:54 schrieb Theodore Ts'o: >> >> Hi Theodore, >> >> >On Wed, Nov 06, 2013 at 12:49:45PM +0100, Stephan Mueller wrote: >> >> Here