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A comment on The first chosen-prefix collision for SHA-1. Parent comment

Re:The first chosen-prefix collision for SHA-1 by SAI_Peregrinus on Tuesday January 07, 2020 @02:07PM (#21983434)
To be excessively pedantic you can encrypt securely (but slowly for the SHA series) with a hash function of sufficient capacity by running the hash function in CTR mode. You turn it into a stream cipher. Ideally you also MAC the ciphertext, nonce, and other associated data. That's is pretty easy with such a hash function (either use HMAC or a MAC mode of the hash function if supported).

Salsa20 & ChaCha20 cores are hash functions (though not collision-resistant compression functions since it's not needed for their design goal and would be slower) run in CTR mode.[1]

[1] https://cr.yp.to/salsa20.html

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Re:The first chosen-prefix collision for SHA-1 by caspper69 on Tuesday January 07, 2020 @03:55PM (#21984715)
> To be excessively pedantic

This is the best, most delicious, type of pedantry friend!

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Re:The first chosen-prefix collision for SHA-1 by smichel17 on Wednesday January 08, 2020 @12:07AM (#21988533)
You're the best kind of pedantry friend!

(Just some more pedantry, friend.)

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Re:The first chosen-prefix collision for SHA-1 by caspper69 on Wednesday January 08, 2020 @06:36AM (#21990490)
Ok man, now that's just over the top.

/s

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