David Wong

cryptologie.net

cryptography, security, and random thoughts

Hey! I'm David, cofounder of zkSecurity, research advisor at Archetype, and author of the Real-World Cryptography book. I was previously a cryptography architect of Mina at O(1) Labs, the security lead for Libra/Diem at Facebook, and a security engineer at the Cryptography Services of NCC Group. Welcome to my blog about cryptography, security, and other related topics.

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A hash function does not provide integrity!

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Some of you might have seen the answer of this famous stack overflow question what are the differences between a digital signature, a mac and a hash?:

hash vs mac vs signatures

The above table is from the most upvoted answer –but it is false. A hash function does not provide integrity, a MAC provides integrity.

Instead a cryptographic hash function provides three properties, well defined in the world of cryptography: collision resistance, pre-image resistance and second pre-image resistance. Nothing else.

suggested reads:
← back to all posts blog • 2017-04-21
currently reading:
A hash function does not provide integrity!
04-21 blog
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