Camelia, the Perl 6 bug

IRC log for #etools, 2012-07-24

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All times shown according to UTC.

Time Nick Message
01:54 snadge hows this sound for a relatively dodgy solution for feeding entropy from a hardware rng, into a guest virtual machine
01:55 snadge xinetd, set up to cat /dev/qrandom (the char device for the hwrng) over a tcp socket
01:56 snadge then the client.. inside the guest, runs a shell script which uses netcat to connect to that port.. and redirect its output to rngd
01:57 snadge as much as that solution makes me cringe.. its probably less dodgy than entropy broker, im not sure if you're familiar with it
02:38 mikemol I haven't messed with the entropy broker.
02:38 mikemol But what you're talking about is something I've done.
02:38 mikemol I had machines on my home network netcat all their entropy to one machine, which then netcatted its entropy to my server.
02:39 snadge im kinda wondering whether the cat eventually blocks on write
02:39 snadge or whether it just keeps spewing indefinitely
02:39 mikemol Pay very careful attention to the parameters of nc.
02:39 mikemol In particular, you're interested in Nagle's Algorithm.
02:39 mikemol It'll have a side consequence of causing a lot of buffering in your sending nc instance.
02:40 snadge right.. what i would imagine it *should* do.. is block on write
02:40 snadge after its filled up some kind of buffer
02:40 mikemol Everything in the pipeline will, including rngd.
02:40 snadge right.. because rngd doesn't just continuosly read .. it only reads when it needs to
02:41 snadge so i was kind of imagining a scenario where its like a bath tub
02:41 snadge that you're pouring water into
02:41 mikemol There's a program named 'buffer' which you can use for that purpose.
02:41 snadge you dont want it to just keep filling regardless of whether its being emptied or not
02:41 mikemol I combined that with a fifo to give a serverside buffer.
02:42 mikemol And be aware of the parameters you have for rngd. By default, it'll only poll the kernel entropy pool every 30s. That's nowhere near enough for anything that rapidly consumes entropy.
02:42 snadge given that this is intended to be used locally.. ie the server and clients are on the same machine
02:42 snadge the buffer only needs to be quite small
02:42 mikemol Also, the version of rngd which will read from the 'file' source is a Debian-specific thing. They've got Debian-specific patches which didn't get merged upstream.
02:43 mikemol Anyway, I've got to get to sleep.
02:43 mikemol g'night.
02:43 snadge gnite
02:43 snadge i'll be using centos.. i think they have the same patch now.. im not sure
05:54 mikemol joined #etools
15:11 mikemol joined #etools

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