Woodstock
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If ChaCha20 is being used just as a CSPRNG, is nonce needed?
3 votes

No it doesn't matter, as you won't be switching the nonce on a per message basis, just outputting a stream of random data. However, remember, your key will only produce an output stream valid until ...

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Why does EdDSA require a b-bit private key instead of b/2-bit?
3 votes

The reason the private key is approximately the same order as the curve is due to the number of possible public keys being equal to the order of the cyclic subgroup generated by G. This varies from ...

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How many bits of entropy can I expect from /dev/urandom in iOS?
2 votes

I mailed Craig Federighi recently about this, concerned that macOS wasn’t capable of generating >128bit quality keys. He responded! “The source you were referencing is out of date. You can find ...

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Why is Curve25519 mostly used for key exchange?
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1 votes

A number of reasons contribute to this. Curve25519 has a non-governmental origin. It's a curve that's very safe by design, and impregnable to many side-channel and other weaknesses that other ...

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Fully Homomorphic Encryption - state of the art
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1 votes

I guess the latest real production grade homomorphic library is Microsoft SEAL, which implements the BFV and the CKKS encryption schemes. I'm not a big MS fan. There are other options to explore: ...

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Can DNA computing to solve elliptic curve algorithms using this method
1 votes

No, DNA computing doesn't harness quantum phenomenon to achieve parallelisation/quantum speedup, DNA computing still falls under the classical classification. Landauer's principle asserts that ...

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Does concatinating mutliple digests of hashes from CSRN result in a CSRN?
Accepted answer
1 votes

Yes it most certainly is, on the assumption that the hashing algorithm used is cryptographically secure and uniform in its output. As a thought experiment, consider that after Elliptic Curve Diffie ...

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Is it OK to just hash a symmetric key to derive an authentication key?
Accepted answer
1 votes

Yes this is "OK". Please correct me if I'm wrong there. You are correct. It's effectively ratcheting the original key. However there may be a more elegant solution such as using static keys for ...

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Generating Private Keys
0 votes

You should definitely stick with Python or my fav, SageMath (which is Python based) when playing with elliptic curve crypto. The private key is generally just a large scalar value, which when ...

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Generate private key from public key RSA
Accepted answer
-1 votes

Take the server’s public key. Parse the modulus and public exponent. (A public key contains the public exponent and modulus) Factor the modulus into p and q elements. Calculate the private key ...

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