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dequis / bitlbee-old

Old personal fork, use https://github.com/bitlbee/bitlbee instead
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Use /dev/urandom properly, don't bother trying /dev/random first #26

Closed dequis closed 9 years ago

dequis commented 10 years ago

See http://www.2uo.de/myths-about-urandom/ for details.

Also add clarifications in the few uses of the libc rand() - it looks horribly insecure with no context but it's just a fallback.

dequis commented 10 years ago

Considered this:

https://developer.gnome.org/glib/stable/glib-Random-Numbers.html

But oddly enough, for cryptographic purposes they recommend platform specific code, like /dev/urandom, which is what we're using.

It's probably as bad as the libc rand(), or maybe slightly better, but i see no easy way to get bytes out of it, or reset the seed of g_random_int() on fork without using GRand instances. Doesn't seem worth it.

jcopenha commented 10 years ago

My suggestion would be to check for /dev/urandom at configure time and fail to build if it isn't there. And if for some reason /dev/urandom goes away after it's built just fail. Having a random_bytes function that sometimes returns bytes that are okay and sometimes aren't is a bad idea.

dequis commented 10 years ago

Not a fan of checking it at configure time, but yeah... silently returning bad random numbers in some platforms is awful.

This patch does improve the situation a little, though

Could also consider using the RNG from the ssl library.

dequis commented 9 years ago

---> https://github.com/bitlbee/bitlbee/pull/7