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Date:   Tue, 12 Oct 2021 13:30:46 -0400
From:   "Theodore Ts'o" <tytso@mit.edu>
To:     Avi Deitcher <avi@deitcher.net>
Cc:     linux-ext4@vger.kernel.org
Subject: Re: algorithm for half-md4 used in htree directories
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On Mon, Oct 11, 2021 at 07:58:00PM -0700, Avi Deitcher wrote:
> Aha. I missed that the seed is injected into buf before passing it
> into half_md4_transform. I was looking at it as just the empty buffer
> before the first iteration of the loop (or, in my case, since I was
> testing with a 6 char filename, the only iteration).
> 
> I will repeat my experiment with that and see if I can tease it out.

BTW, if you are looking for a userspace implementation of the hash,
it's available in libext2fs in e2fsprogs.

Cheers,

					- Ted