Stack Overflow
Stack Overflow

Questions tagged [elliptic-curve]

In mathematics, an elliptic curve is a smooth, projective algebraic curve of genus one, on which there is a specified point O.

In mathematics, an elliptic curve is a smooth, projective algebraic curve of genus one, on which there is a specified point O (the point at infinity). An elliptic curve is in fact an abelian variety — that is, it is a (necessarily commutative) group with respect to an algebraically defined multiplication — and O serves as the identity element. Often the curve itself, without O specified, is called an elliptic curve.

685 questions
0
votes
1 answer

Problem "EXCEPTION NOT FOUND" in Cryptography (Python)

CODE start_time1 = time.time() ec = EC(a, b, num) g, _ = ec.at(at) assert ec.order(g) <= ec.q # ElGamal enc/dec usage eg = ElGamal(ec, g) # mapping value to ec point # "masking": value k to point ec.mul(g, k) # ("imbedding" on proper…
Jaivardhan Singh
  • 1
  • 1
0
votes
0 answers

Should shared secret be hashed (SHA-256) in ECDH?

FIDO2 uses ECDH (elliptic curve diffie hellman) for key agreement. However, in its sequence diagram, I see they hash the shared secret using SHA-256. Is there any specific reason to use the hash instead of the shared secret itself? Here is the FIDO…
Mohammad Siavashi
  • 1,192
  • 2
  • 17
  • 48
0
votes
1 answer

ECIES secure mode and padding scheme for ECC Algorithm -Java

What is the best secure mode and padding scheme for ECIES replacement. Cipher c = Cipher.getInstance("ECIES"); public static byte[] eccEnc(String msg,String pub) throws NoSuchPaddingException, NoSuchAlgorithmException, IllegalBlockSizeException,…
Varun
  • 196
  • 1
  • 20
0
votes
0 answers

What does it mean to encrypt from a key to a key?

I'm trying to understand the key exchange happening with CurveMQ described here. http://curvezmq.org/page:read-the-docs My understanding of public key cryptography is you use a public key to encrypt data that can then be decrypted by the…
Dustin Butler
  • 818
  • 7
  • 22
0
votes
0 answers

Bouncy Castle 1.47 - PGP Support for EC keys

Currently my application supports BouncyCastle 1.47. I am able to generate the EC Key pair but fails in wrapping up in the PGPKeypair. package org.bouncycastle.bcpg; /** * Public Key Algorithm tag numbers */ public interface…
Vicky
  • 1
  • 2
0
votes
1 answer

Alphabets in x , y coordinates of Elliptic graph

I was reading about the ethereum address generation process. I am very confused that when Private key generated is processed under "Elliptic Curve Digital Signature Algorithm" , we get a public key which is a point on graph. We take x & y…
Brijesh Roy
  • 3
  • 3
0
votes
1 answer

BouncyCastle gets error 'public key presented not for certificate signature' for retrieved ECPublicKey

I am trying to use BouncyCastle library for generating X509Certificate in a .Net application, meanwhile i want to use keys stored in HSM. My solution is generating EC key-pair in HSM, returning ECPoint and key lable to .Net application, and…
morteza
  • 125
  • 11
0
votes
1 answer

GCP KMS - Elliptic curve Signature

I am using google cloud KMS to manage my keys. Using JAVA client libs to interact with KMS. I receive byte array as a signature of a message as below byte[] plaintext = message.getBytes(StandardCharsets.UTF_8); // Calculate the…
neo007
  • 27
  • 7
0
votes
0 answers

Retrieve supported elliptic curves

I would like to know if it is possible to find the supported elliptic curves in ruby? by searching in the OpenSSL gem it doesn't seem possible. The tmp_key method does not really return information. For example, with www.google.com I get X25519…
JoMar
  • 13
  • 2
0
votes
1 answer

Given a Java ECPublicKey ECDSA PublicKey, how can I build an SSH2 public key?

I have created a ECDSA key and now need to convert this to SSH2 key. final KeyPairGenerator keyGen = KeyPairGenerator.getInstance("ECDSA"); ECGenParameterSpec params = new ECGenParameterSpec("secp384r1"); keyGen.initialize(params); …
Vicky
  • 1
  • 2
0
votes
1 answer

EXC_BAD_ACCESS code=257 at SecKeyIsAlgorithmSupported

I have a KeyChain class where I sign a string. I got Thread 8: EXC_BAD_ACCESS (code=257, address=0x3fd574bc6a7ef9db) error at SecKeyIsAlgorithmSupported function. I could not figure out why this error pops up. When I use the getquery variable which…
Hilal
  • 902
  • 2
  • 22
  • 47
0
votes
1 answer

Elliptic Curve encryption and decryption on Solidity and Python

I am trying to create a smart contract where I have to encrypt (and decrypt) data that I receive from a Python script running on a client. The data will be encrypted on the client-side, and I will have to decrypt it on the smart contract. I got a…
Arka Seth
  • 5
  • 3
0
votes
0 answers

Installing MIRACL Library in Macbook air M1

I am trying to install MIRACL Library in my Macbook Air with M1 chip. I cloned the repository from https://github.com/miracl/MIRACL and followed the instructions from…
Arivarasan
  • 285
  • 1
  • 7
0
votes
1 answer

Nodejs crypto: Elliptic Curve to sign message and export public key as text

I want to achieve the following with the Nodejs crypto module: I want to sign a message with my private key on a defined EC and have the signature as raw buffer/hex. I want to have the respective public key as raw buffer/hex. I can achieve both…
hagen
  • 3
  • 4
0
votes
0 answers

Using a Known Nonce to Derive Private Key From Nonce, Signature and Message

I am trying to derive a private key using the formula below: The inputs are: r & s are from the signature. H(m) is a hash of the message being signed. k is the nonce used to sign the message. Below is my code implementation using the npm elliptic…
Isaac Byrne
  • 603
  • 1
  • 7
  • 19
1 2 3
…
45 46