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by 0x0 3971 days ago
Isn't the main purpose of a hashing function to validate file (edit: or "message") integrity? so you want them to process as many MB/s as possible?

I thought using hashing to save passwords is misusing cryptographic hashes for something they were not intended to do? (Assuming they will keep the input secret as opposed to preventing finding colliding duplicate inputs?)
1 comments
laumars 3971 days ago
Collision attacks is a non-issue with modern hashes.

The point of hashing passwords is it's a one-way cither. ie can't be unencrypted - can only be brute forced or rainbow table attacked (the latter is where salts and peppers come into the equation).

https://en.wikipedia.org/wiki/Cryptographic_hash_function

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schoen 3971 days ago
You keep defining "cryptographic" hashing as equivalent to password hashing, but password hashing is only one application of cryptographic hashing (a minority application). A hash function is still "cryptographic" and its applications are still "cryptographic applications" when they aren't password-related. Those applications commonly optimize for speed, rather than pessimizing for speed. In many of those contexts, the input to the hash and the hash value are presented simultaneously to the verifying party (or aren't even secret); in those contexts there is no benefit at all from making the cryptographic hash function slow to compute, and considerable benefit from making it fast to compute.
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laumars 3971 days ago
As per https://news.ycombinator.com/item?id=10012384:

I didn't make that assumption. I exampled one use of cryptographic hashes as being for password hashing. An example is not the same as saying two things are the same.

I've possibly expressed myself rather poorly, but I think quite a few people on here have made some incorrect assumptions about the point I was raising.

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