[Cryptography] Finding Entropy Isn't That Hard

2013-09-13 Thread Kent Borg
On 09/11/2013 07:18 PM, Perry E. Metzger wrote: the world's routers, servers, etc. do not have good sources, especially at first boot time, and for customer NAT boxes and the like the price points are vicious. I agree that things like consumer NAT boxes have a tricky problem, and anything

Re: [Cryptography] Finding Entropy Isn't That Hard

2013-09-13 Thread Kent Borg
On 09/12/2013 10:41 AM, Kent Borg wrote: routers and servers are not as bad off as people say. Not that more sources is bad. A new trustworthy HW entropy source would be good. Even a suspect rdrand is worth XORing in (as Linux does on the machine I am using right now). But if you thirst

Re: [Cryptography] Finding Entropy Isn't That Hard

2013-09-13 Thread Marcus Leech
[* Until Linux kernel 3.6 the person maintaining urandom was busily turning off interrupts as a source of entropy, I think because he didn't know how much entropy he was getting so better not to get it at all (huh?). In 3.6 this was changed to use all interrupts as entropy sources, which is

Re: [Cryptography] Finding Entropy Isn't That Hard

2013-09-13 Thread Kent Borg
On 09/13/2013 11:59 AM, Marcus Leech wrote: Any physical-world sensor driver, where the sensor inherently has a bit of noise, I think has a moral obligation to contribute bits to the kernel entopy pool. Within limits. Mixing the entropy pool on Linux takes work and battery power. Looking