Re: [kernel-hardening] Re: [PATCH v7 3/6] random: use SipHash in place of MD5

[Jason A. Donenfeld]

On Thu, Dec 22, 2016 at 7:08 PM, Hannes Frederic Sowa
<hannes@xxxxxxxxxxxxxxxxxxx> wrote:
> I wasn't concerned about performance but more about DoS resilience. I
> wonder how safe half md4 actually is in terms of allowing users to
> generate long hash chains in the filesystem (in terms of length
> extension attacks against half_md4).

AFAIK, this is a real vulnerability that needs to be addressed.

Judging by Ted's inquiry about my siphash testing suite, I assume he's
probably tinkering around with it as we speak. :)


Meanwhile I've separated things into several trees:

1. chacha20 rng, already submitted:
https://git.zx2c4.com/linux-dev/log/?h=random-next

2. md5 cleanup, not yet submitted:
https://git.zx2c4.com/linux-dev/log/?h=md5-cleanup

3. md4 cleanup, already submitted:
https://git.zx2c4.com/linux-dev/log/?h=ext4-next-md4-cleanup

4. siphash and networking, not yet submitted as a x/4 series:
https://git.zx2c4.com/linux-dev/log/?h=net-next-siphash

I'll submit (4) in a couple of days, waiting for any comments on the
existing patch-set.

Jason