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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.

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How can I generate a valid ECDSA EC key pair?

I am trying to generate ECDSA key pair using SpongyCastle in Android. This is the code: static { Security.insertProviderAt(new org.spongycastle.jce.provider.BouncyCastleProvider(), 1); } public static KeyPair generate() { …
snewtMs
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Can WINE handle ECC certificates?

I have an application that supposedly runs well under Mono, but is having some problems on my system. In the meantime, I tried running it through WINE after using winetricks to install the proper version of .NET (winetricks dotnet452). This worked…
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Unattended generation of an ECDSA key using gpg2

Short question How do I specify an elliptic curve in a gpg2 v2.1.11 parameter file? Long question I have successfully used the following bash script to generate an RSA key using gpg2 v2.1.11: #!/bin/bash PUBRING_FILE=$(mktemp…
user2768
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Elliptic curve point addition using bouncycastle

My problem is very straightforward: I need to add two points over Fp using Java. As soon as java api lacks some ecc utils I'm using bouncycastle. Here is the formulas used: P + Q = -R α = (yq - yp)/(xq-xp) уr = -yp + α(xp - xr) xr = α^2 - xp -…
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Rejecting class because it failed compile-time verification

I am trying to integrate curve25519-java from openwhispersystems into my Android app and compiling it with API 23 (Marshmallow). When using non native code I get this runtime exception: java.lang.VerifyError: Rejecting class…
Alex Amiryan
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brainpool320r1 Elliptic Curve not supported in Java Card?

I am working on a Java Card 3.0.1 applet on which I use ECC. My card supports ECC GF(p) up to 320bits, so I tried to use the brainpool320r1 elliptic curve (parameters). The problem is that I get a CryptoException that I don't understand... It is the…
Raoul722
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Use previously generated private key in ECIES

I wan to encrypt /decrypt data using ECIES , I am using cryptopp for this. AutoSeededRandomPool prng; //get private key generated ECIES::Decryptor d0(prng, ASN1::secp256r1()); PrintPrivateKey(d0.GetKey()); //get public key…
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Recovering an ECPublicKey from JavaCard to Java

I am trying to implement ECDH between a terminal (simulated by my computer) and a smart card (Java Card). I fixed the elliptic curve that I want to use, and on the card side I have the following code to run the first part of the protocol : …
Raoul722
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Find point and elliptic curve given the public key

I'm trying to resolve this problem. Once the public key is known, I want to know which point and elliptic curve was used to generate that public key. For example, given this ECC public key: 04 6b fb ee c6 9d e7 2c 66 a6 68 ec e1 aa f1 a2 64 a3 c9…
avm_69
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Use python library in iOS

I want to use a python library https://github.com/yann2192/pyelliptic in iOS to encrypt/decrypt. I've gone through the following posts: Is that possible to run a python built program on iOS as a static lib? Embedding Python in an iPhone app But…
SandeepAggarwal
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How to sign the Certificates with Elliptic curve private keys and ECDSA algorithm?

I am able to sign the certificates using bouncy castle with RSA private Keys and "SHA256withRSA " algorithm. I have used below link for reference to achieve this. Sign CSR using Bouncy Castle Now I have my CAs with Elliptic Curve keys signed with…
Dnyanesh
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How to perform ECKA and have an ECPoint returned?

I'm using Bouncy Castle to perform the Elliptic Curve Key Aggreement using the ECDH protocol in a smart card related software, as defined in the BSI-TR-03111 specs, §3.4 with The purpose is to perform the Generic Mapping of the nonce in the PACE…
Dek Dekku
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Javacard KeyAgreement differs from BouncyCastle KeyAgreement

My problem looks like this. I have generated keys on the card and the terminal sides. I have on the terminal side the card public and private keys and the terminals public and private keys, and the same on the card side (i'm doing tests so thats why…
TajnosAgentos
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Read EC public key from .pem file in C

I generated a EC public and private key pair using: openssl ecparam -name prime256v1 -genkey -noout -out ecprikey.pem openssl ec -in ecprikey.pem -pubout -out ecpubkey.pem I want to read the public key into a byte array in C. How do I go about it?…
previouslyactualname
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Obtaining a signed x509 when using ECDSA keys

I am trying to sign some X509 certificates. My root private key is an ECDSA secp384r1. I am using bouncy castle. What seems to happen is that when generating the certificate signature, the Signature class used is unable to understand my ECDSA…
laura
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