# Tag Info

### How can we reverse Elliptic Curves after solving the DLP problem?

The first thing to do in such a case would be to test that your method really achieves something new by replicating existing prime field DLog records. At the time of writing, the largest public ...
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### Are curve secp256k1 ECDSA signatures distinguishable from random data?

We know that the standard encoding of points of an elliptic curve is not uniformly random since they must satisfy the curve equation. In another look, we don't have $2*p^2$ points, and if we consider ...
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### Is the elliptic-curve cryptography library libsecp256k1 not susceptible to the Hertzbleed attack?

It's really much too early to make a definitive statement one way or the other on this. The information leakage is based on a feature of some CISC architectures to allow a variable clockrate depending ...
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### Is there a relationship between the secp256k1 public key of the sum of two private keys, and the public keys of those original two private keys?

If I have two secp256k1 private keys and add them together, can I derive the public key for the sum, if I only know the public keys for the two original private keys? Yes. While the idea of 'public ...
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### Are curve secp256k1 ECDSA signatures distinguishable from random data?

Reformulating slightly1: Can we distinguish from 64-byte of random data an ECDSA signature (without ASN.1 formatting) for curve secp256k1, unknown random key pair and message? Yes, with excellent ...
• 142k
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### When incrementing a private key by 1, by how much is the public key Incremented?

If you have a secp256k1 keypair and you increment the private key by 1, what's a fast way to compute the new public key? Using notation close to sec1 and the parameters of secp256k1, if the private ...
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### How can we reverse Elliptic Curves after solving the DLP problem?

We can make a valid analogy between solving $5^x \bmod 17 = 13$ and breaking Elliptic Curve cryptography on secp256k1: $x$ is a Private Key $13$ is the matching Public Key $17$ is the curve's ...
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### In Bitcoin, given half the 52-character private key in WIF format, is it possible to reconstruct the whole private key?

We must first wonder if the preconditions hold, in particular 1; that is: In Bitcoin, given half the 52-character private key in WIF format, is it possible to reconstruct the whole private key? The ...

### Modulo p in Elliptic Curve Cryptography

To carry out Elliptic Curve Cryptography between parties, are all elliptic curve equations considered to be in the form $\bmod p$? Yes for secp256k1 when it comes to point coordinates, but not for ...
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### Is it possible to calculate the modular inverse of a secp256k1 public key?

This is a bit extended answer; I was wondering if there were any other ways of calculating the modular multiplicative inverse of a point on an elliptic curve (like secp256k1)? Or perhaps a reason ...
• 49k
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### Modulo p in Elliptic Curve Cryptography

The prime in the definition of the curve Secp256k1 The prime $p$ is part of the curve design, analysis, and definition that defines the $\mathbb{F_P}$. If someone uses a different $p$ then they have ...
• 49k
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### Possible to directly calculate the Recovery ID from a msg, signature and public key in ECDSA/secp256k1?

Unfortunately I don't think that is possible without just testing which one works. That is because $[s]R$ and $[-s](-R)$ are the same curve point, and both $R$ and $-R$ have the same x-coordinate $r$, ...
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### secp256k1: is it theoretically possible to generate same signature with different key, message hash and k?

It is totally possible and fairly easy to see without any advanced maths. The curve has order n (n Points in the curve) the private key d is [0... n-1] and the random number k [1... n-1] and there are ...
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### How to choose secp256k1 private key?

You are confusing the concepts; the private key vs the public key. Your private key $k$ is an integer which is selected uniform randomly between $1$ to order of the base point $G$, $k \in[1,n-1]$. ...
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