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5

OK, so the first issue is: do you need these rolls to be reproducible and predictable? That is, do you need to be able to fast-forward to the 10000th roll or rewind to the 20th, and get the same result? If you don't need that feature, then why not use a cryptographically secure random number generator instead? This way, neither you nor an attacker can ...


3

I want to make a few points in addition to @NeilSmithline's excellent answer. Taking a 256-bit random value and hashing it with SHA-256, the output will still have (roughly) 256 bits of entropy. I say "roughly" because it's an open problem whether SHA256 actually maps to every possible string on 256 bits - but for all practical purposes, it's close enough. ...


4

Yes. Salt is used to prevent precomputation attacks, but random 256 bit strings are too large for precomputation. Slow hash functions with many iterations are meant to slow down dictionary attacks, but random 256 bit strings are too big for a dictionary or for exhaustive testing. So a single SHA256 hash is secure for long, cryptographically secure random ...


3

The technical answer is actually "no, because SHA-256 with RSA-2048 Encryption is not a certificate hashing algorithm. However, SHA-256 is a perfectly good secure hashing algorithm and quite suitable for use on certificates, and 2048-bit RSA is a good signing algorithm (signing is not the same as encrypting). Using 2048-bit RSA with SHA-256 is a secure ...



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