Stack Overflow
Stack Overflow

Questions tagged [ecdsa]

In cryptography, the Elliptic Curve Digital Signature Algorithm offers a variant of the Digital Signature Algorithm which uses elliptic curve cryptography.

Elliptic Curve Digital Signature is a variant of algorithms. It allows in some cases a smaller public key (for instance, 160 bit in ecdsa compared to 1024 bit in dsa for 80 but security level), and requires the two sides to agree on a curve's field and equation, as well as a prime order on the curve and a multiplicative of the order.

Wikipedia description of Elliptic Curve Digital Signature

700 questions
0
votes
0 answers

C++ - OpenSSL - secp256k1 Keypair test not working on website - also unsure how to sign and verify using a string

I have the following code for printing and generating a public and private key: #include #include #include int main() { BIO* outbio = NULL; EC_KEY* myecc = NULL; EVP_PKEY* pkey = NULL; …
user5057712
0
votes
1 answer

Is there any API endpoint to generate and sign EC key pairs

My actual need is to generate a EC key pair (public & private key) and use it to mock the device authorization. Once the generated public key is used in one of our endpoints, I will receive an SMS TAN for which I will need to generate a signature…
Karthik Ravindran
  • 1
  • 1
0
votes
1 answer

Why do I get "PrehashSignature is not implemented for Signature" error when using k256 library?

I simply tried to create a recoverable signature using the k256 crate documentation as a reference as follows, but for some reason I get a compile error regarding the sign method to create the signature. use k256::ecdsa::{recoverable,…
user76333
  • 153
  • 1
  • 13
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
0
votes
0 answers

How to derive the message from ECDSA Signature value

Is there any way to derive the message from ECDSA Signature value, like online tools or with PHP for test only, because I have this Signature MEUCIH+9yjWRCSWYVW1Tk6hLE91iR8NiVetvz17C3k6ZTJo8AiEAiHe6OK7iyxjUVjpU5RKZjgXgWYP5LjdFsoE5GTB4cIA= and want…
MK Said
  • 165
  • 8
0
votes
1 answer

Elliptic Curve Cryptography (ECDSA) Private Key Matches Public Key (Java - Bouncy Castle)

I try to use Elliptic Curve Digital Signature Algorithm (ECDSA) with Bouncy Castle and Java. I want to generate a public key and private key. The problem is that these keys have the exact same values. Let's look at the code: KeyPairGenerator…
balazsh
  • 17
  • 3
0
votes
0 answers

AWS-KMS signature always changing

I'm currently exploring to generate private keys on kms, I already get the public key, however every time I use KMS.SignRequest with the same message, it generate different signature. was that the expected output? I thought it should be the…
Lonewarp
  • 1
0
votes
1 answer

How to verify signature with x509 certificate using EC-key in c# payconiq

I'm trying to verify a signature I get in the callback of Payconiq (payment-platform) The signature is put together based on this logic A JWS represents these logical values separated by dots(.): JOSE Header JWS Payload (Not included) JWS…
Nathan T.
  • 277
  • 1
  • 8
0
votes
1 answer

How to decrypt JWE encrypted with ECDS ( ECDH-ES+A128KW ) algorithm in C#

I have been looking for a way in C# to decrypt JWE tokens encrypted with ECDH-ES+A128KW by my OpenId Connect provider. I have shared the EC public key with OIDC provider and they send me a JWE encrypted using the shared public key. I want to…
Rama
  • 187
  • 1
  • 6
  • 20
0
votes
0 answers

.NET Core 3.1 Ecdsa Generate R, S - Apple client_secret

I am following this guide https://p.agnihotry.com/post/validating_sign_in_with_apple_authorization_code to be able to "server verify" an Apple AuthCode by sending a request to Apple. These below are indications to generate client_secret: Following…
cmarrades
  • 55
  • 9
0
votes
1 answer

java.security.InvalidAlgorithmParameterException on Java 8 but works on Java 11

So let's assume you want to verify a signature using a public key that uses ECDSA algorithm with brainpoolP256r1 elliptic curve. For running the code below, follows these steps: generate a keypair of brainpool using these commands: openssl ecparam…
Florin
  • 55
  • 8
0
votes
0 answers

Remote ssh-rsa fingerprint matches, but ECDSA sha256 and md5 don't?

A question for (primarily) the ssh/crypto experts: I'm trying to validate the identity of a remote ssh server. The server (or appliance) operator has given me fingerprints with various hash algorithms: the fingerprints I was given However, when I…
sark_work
  • 1
  • 2
0
votes
1 answer

Hashed value for xadesSignedProperties not accurate

I have an UBL XML file and need to hash sha256 for xadesSignedProperties and the part need to be hash is : …
MK Said
  • 165
  • 8
0
votes
1 answer

Convert ECDSA secp521r1 private key into PEM format using bouncy castle

We are programatically generating ECDSA private/public key in java as follows: KeyPairGenerator keyPairGenerator = KeyPairGenerator.getInstance("EC"); keyPairGenerator.initialize(new ECGenParameterSpec("secp521r1")); KeyPair keyPair =…
Joyjit
  • 119
  • 1
  • 13
0
votes
0 answers

Is there any way to plot xy diagram of points of elliptic curve over finite field with huge number p defined by standard EC (p-192,p-256...)?

Is there any way to plot xy diagram of points of elliptic curve (such as NIST p-192,p-224,p-256...) over finite field? I tried with p-256, but it has very big number of p thus when I use for loop it takes huge amount of time to go through the loop.…
Alokin
  • 9
  • 2
1 2 3
…
46 47