16 questions linked to/from Curve25519 Key Validation
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### Formatting first/last byte of curve25519 private key? [duplicate]

Can anyone dumb it down for me on why you would need to format the first and last byte of a random number to properly generate a curve25519 private key as noted in 'Computing secret keys' section of ...
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### How to create an EC point from a plaintext message for encryption

It seems that ElGamal encryption is also possible for Elliptic Curve cryptography. However, that requires the user to convert the message to a point on the curve. What strategies are there to derive a ...
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### Is the STARK Curve a SafeCurve?

SafeCurves defines criterias for choosing safe curves in elliptic-curve cryptography. STARK Curve defines a Stark-friendly elliptic curve that can be used with ECDSA. I was wondering: Is the STARK ...
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### Ed25519 to X25519 transportation

Using montgomeryX = (edwardsY + 1)*inverse(1 - edwardsY) mod p it is possible to transport an Edwards curve point (Ed25519 ...
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### ed25519 attacks

I try to understand invalid curve attack and small subgroup attack. The lower 3 bits of a ed25519 private key are cleared to be a multiple by 8. So an attacker is unable to gain any information using ...
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### How do I validate Curve448 public keys?

Performing an ECDH calculation with an invalid public key can leak information about your own private key. With Weierstrass curves, it's important to verify that the peer's public key is actually a ...
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### How does sending compressed points in ECC can limit the attacker's capabilities?

While sending an EC point we mainly have two options, send it compressed or uncompressed. The uncompressed has prefix 04 and compressed has ...
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1 vote
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### Are there any public keys for which the private key can be easily derived (ECDSA)?

I know that generally it's infeasible to find the private for any given public key. But I also came across the question "Find ECDSA PrivKey to PubKey = 0", in which it was explained that the ...
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### Whats the reason for using elliptic curves of order |E| = fr

To be more precise, in the books I sometimes see that they just require you that the order of your elliptic curve is $|E| = fr$, where $f$ is some small integer with possible factors, but $r$ is a ...
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### A few questions about the elliptic curves functionalities

I've been learning about the elliptic curves and how they work, and their usage in cryptography, and I'm trying to figure out how to use them using Go. Where is the 'a' parameter from my ECC equation ...
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