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References: <20220923110332.24090-1-unixbhaskar@gmail.com>
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From:   Daniel Mentz <danielmentz@google.com>
Date:   Fri, 23 Sep 2022 11:12:42 -0700
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Subject: Re: [PATCH] kernel:gen_kheaders:Replace md5sum to sha256sum
To:     Bhaskar Chowdhury <unixbhaskar@gmail.com>
Cc:     masahiroy@kernel.org, lkml <linux-kernel@vger.kernel.org>
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On Fri, Sep 23, 2022 at 4:06 AM Bhaskar Chowdhury <unixbhaskar@gmail.com> wrote:
> Thought to apply a better encryption mechanism.

MD5 and SHA256 are secure (or, in the case of MD5, not so secure) hash
algorithms, not encryption mechanisms.

> Replace all occurance of md5sum to sha256sum .

Looking at this script, I'm not convinced that it relies on MD5 being
a cryptophically secure hash function. It appears to me as if this
script uses MD5 to simply detect innocent changes to a set of files as
opposed to guarding against malicious attacks. I also found that
sha256sum takes almost three times longer than md5sum. So, in the
absence of security requirements, md5sum might actually be the better
choice because it's faster.