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From:   <rsbecker@nexbridge.com>
To:     "'Hans Petter Selasky'" <hps@selasky.org>,
        "'Konstantin Ryabitsev'" <konstantin@linuxfoundation.org>
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In-Reply-To: <6061d012-13b7-ca4b-5556-70875b65c887@selasky.org>
Subject: RE: Gitorious should use CRC128 / 256 / 512 instead of SHA-1
Date:   Fri, 13 Jan 2023 10:56:35 -0500
Organization: Nexbridge Inc.
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On January 13, 2023 10:50 AM, Hans Petter Selasky wrote:
>On 1/13/23 16:45, Konstantin Ryabitsev wrote:
>> I think you're misunderstanding some of the core principles of git.
>
>Maybe, I'm usually commandering git via the terminal.
>
>But if you say you can already edit stuff, why does the commit hash need to be
>cryptographic? I don't get that part. Yeah, I think of git commits like blockchain.

git is using SHA1/SHA256 (which happen to be coincidentally cryptographic) as message digests with a very low probability of collisions when the hashes are computed. There is never a situation, implied by cryptography, where there is a decode of a git hash.  In order to make git a blockchain, you would need to implement central signing authorities, which would require a fork if the signature mechanism changes. The signature mechanism (SSH, GPG) is distinct from hash computation in git's trees, but depends on hash integrity.