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On Sat, 2021-07-24 at 17:15 -0400, Joshua Kinard wrote: |
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> On 7/24/2021 11:16, Michał Górny wrote: |
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> > Hi, everyone. |
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> > |
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> > I've been asked to repost the idea of removing SHA512 hash from |
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> > Manifests, effectively limiting them to BLAKE2B. |
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> > |
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> > The 'old' set of Gentoo hashes including SHA512 went live in July 2012. |
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> > In November 2017, we have decided to remove the two other hashes and add |
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> > BLAKE2B in their stead. Today, all Gentoo packages are using BLAKE2B |
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> > and SHA512 hashes. |
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> > |
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> > To all extent, this is purely a cosmetic change. The benefit from |
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> > removing the additional hash is negligible, both from space perspective |
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> > and hashing speed perspective. The benefit from keeping two hashes is |
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> > also negligible. |
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> > |
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> > Back during the 2017 discussion, Infra came to the conclusion that we're |
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> > going to keep SHA512 for a transition period, then remove it, and stay |
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> > with a single hash algorithm. In my opinion, we have kept it long |
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> > enough. |
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> > |
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> > WDYT? |
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> |
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> Are there any security benefits/consequences of keeping two/one? If no to |
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> consequences, then I don't see a problem dropping SHA512. |
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To the best of my knowledge, the consequences are negligible. |
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> And are we looking at BLAKE3 hash support at all for the future? I know |
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> that algo is fairly new (Jan 2020). A quick read indicates it merges a |
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> number of the BLAKE2 variants together and is faster in some areas of execution. |
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Not at the moment. I see they've eventually made a C implementation, so |
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maybe it's worth looking into. OTOH we may want to wait till it's part |
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of CPython, or at least has C-based Python bindings. |
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-- |
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Best regards, |
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Michał Górny |
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