Re: Qemu User Space Binaries and Entropy

No, that's fine. The explanation is good enough for me. I teach a reverse engineering course where we use both user space and system emulation.

When I have extra cycles, I might take a look.

Thank you!

On Thu, Apr 9, 2020 at 9:37 AM Peter Maydell <address@hidden> wrote:

On Thu, 9 Apr 2020 at 14:17, Heather Eacmen <address@hidden> wrote:
> Long story short, I'm trying to figure out why my "qemu-mipsel" (version 3.1.1.1) is able to start up SSL for my webserver, when the "qemu-mipsel" (version 2.6 and 2.11) both require the /dev/random or /dev/urandom to be created/generated.
>
> What is happening under the hood? I took a look at change logs between 2.11 and 3.1.1.1 - I could not ascertain what change could have allowed 3.1.1.1 to find entropy. I could have very well misinterpreted or misunderstood how things work.

My first guess was that this would have been when we
implemented the getrandom syscall, which allows applications
to get randomness without having to open /dev/random or
/dev/urandom. However that went in I think in 2.6, so it
can't be that.

If the answer matters to you you could run a git bisect to
find out which commit changed this behaviour.

thanks
-- PMM

From:	Heather Eacmen
Subject:	Re: Qemu User Space Binaries and Entropy
Date:	Thu, 9 Apr 2020 11:48:29 -0400